inter partes - fish & richardson’s post-grant practice · 2017-04-22 · 1:15-cv-10374, filed...

UNITED STATES PATENT AND TRADEMARK OFFICE

____________________

BEFORE THE PATENT TRIAL AND APPEAL BOARD

____________________

MICRON TECHNOLOGY, INC., AND MICRON MEMORY JAPAN, INC., Petitioners

v.

MASSACHUSETTS INSTITUTE OF TECHNOLOGY Patent Owner

____________________

Case: IPR2015-01087 U.S. Patent No. 6,057,221 ____________________

PETITION FOR INTER PARTES REVIEW

Mail Stop PATENT BOARD Patent Trial and Appeal Board U.S. Patent and Trademark Office P.O. Box 1450 Alexandria, VA 22313-1450 Submitted Electronically via the Patent Review Processing System

Petition for Inter Partes Review of U.S. Patent No. 6,057,221 IPR2015-01087

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TABLE OF CONTENTS

I. MANDATORY NOTICES UNDER 37 C.F.R. § 42.8(A)(1) ................................................ 1

A. Related Matters under 37 C.F.R. § 42.8(b)(2) .........................................................1

B. Real Party-In-Interest under 37 C.F.R. § 42.8(b)(1) ................................................1

C. Counsel and Service Information .............................................................................2

II. PAYMENT OF FEES — 37 C.F.R. § 42.103 ......................................................................... 2

III. TECHNOLOGY BACKGROUND ......................................................................................... 2

IV. REQUIREMENTS FOR IPR UNDER 37 C.F.R. §§ 42.104 ................................................. 3

A. Grounds for Standing Under 37 C.F.R. § 42.104(a) ................................................3

B. Identification of Challenge Under 37 C.F.R. § 42.104(b) .......................................3

C. Level of Ordinary Skill in the Art ............................................................................6

D. Claim Construction under 37 C.F.R. §§ 42.104(b)(3) .............................................6

V. SUMMARY OF THE ’221 PATENT ..................................................................................... 8

VI. THE CHALLENGED CLAIMS ............................................................................................ 10

VII. PRIOR PROSECUTION ........................................................................................................ 12

VIII. HOW THE CHALLENGED CLAIMS ARE UNPATENTABLE ...................................... 14

A. Ground 1: Claims 3-4, 6-8, 23, 25-26 and 28 Are Anticipated Under § 102(a) by Koyou ......................................................................................14

1. The disclosure of Koyou ............................................................................14

2. Koyou anticipates independent claim 3 .....................................................17

3. Koyou anticipates dependent claims 4, 6-8, 23 and 25 ..............................26

4. Koyou anticipates independent claim 26 and dependent claim 28 ......................................................................................................30

B. Grounds 2 and 3: Claims 14-15 and 29 are Obvious under § 103(a) over Wada either in view of Lou (Ground 2) or in view Billig (Ground 3), Combined with General Knowledge in the Art .................................31

1. The disclosure of Wada .............................................................................32

2. The disclosure of Lou ................................................................................34

3. The disclosure of Billig ..............................................................................36

4. Wada and either of Lou or Billig, combined with general knowledge in the art, disclose every limitation of claim 14 ......................36


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5. Wada and either of Lou or Billig, combined with general knowledge in the art, disclose every limitation of dependent claims 15 and 29 ........................................................................................41

6. A person of ordinary skill in the art would have been motivated to combine the teachings of Wada, either of Lou or Billig, and the general knowledge in the art, thereby rendering claims 14, 15 and 29 obvious ....................................................42

7. Patent Owner’s reexamination arguments do not overcome unpatentability over Wada, either of Lou or Billig, and the general knowledge in the art ......................................................................44

C. Ground 4: Claims 3-4, 6-8, 23, 25-26 and 28 are Obvious under § 103(a) over Koyou in View of Wada, Combined with General Knowledge in the Art .............................................................................................46

1. Koyou and Wada, combined with general knowledge in the art, disclose every limitation of claims 3-4, 6-8, 23, 25-26, and 28 .........................................................................................................47

2. Motivation to combine Koyou, Wada, and the general knowledge in the field is found in the references themselves and in the general prior art ......................................................50

3. Patent Owner’s reexamination arguments do not overcome unpatentability over Koyou and Wada ......................................................52

D. Grounds 5 and 6: Claims 13, 17-18, 21-22, 24, 27, and 30 are Obvious under § 103(a) over Koyou either in view of Lou (Ground 5) or in view of Billig (Ground 6) ..........................................................................57

E. Grounds 7 and 8: Claims 13, 17-18, 21-22, 24, 27, and 30 are Obvious under § 103(a) over Koyou in view of Wada and in further view of either Lou (Ground 7) or Billig (Ground 8), Combined with General Knowledge in the Art .....................................................59

IX. CONCLUSION ...................................................................................................................... 60


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TABLE OF EXHIBITS

Exhibit # Exhibit Description

(Citation is to page, column, or paragraph in original, except for Exhibits 1009, for which citation is to inserted page number)

1001 Declaration of Dr. Michael Thomas

1002 Curriculum Vitae of Dr. Michael Thomas

1003 U.S. Patent No. 6,057,221

1004 File History for U.S. Patent No. 6,057,221

1005 The New IEEE Standard Dictionary of Electrical and Electronic Terms, Fifth Ed., Institute of Electrical and Electronics Engineers, Inc., New York (1993)

1006 Japan Pat. Appl. Publ. No. 8-213465 to Koyou (including English translation and supporting declaration)

1007 Japan Pat. Appl. Publ. No. 6-244285 to Wada, et al. (including English translation and supporting declaration)

1008 U.S. Patent No. 5,729,042 to Lou et al.

1009 U.S. Patent Application No. 514,800 filed August 14, 1995 (to which U.S. Pat. No. 5,729,042 claims priority)

1010 U.S. Patent No. 5,025,300 to Billig et al.

1011 Ex Parte Reexamination Application No. 90/011,607, Request for Ex Parte Reexamination filed March 30, 2011

1012 Ex Parte Reexamination Application No. 90/011,607, Corrected Pre-amendment under 35 C.F.R. 1.530 filed April 14, 2011

1013 Ex Parte Reexamination Application No. 90/011,607, Order Granting Request for Ex Parte Reexamination filed June 23, 2011

1014 Ex Parte Reexamination Application No. 90/011,607, Non-Final Office Action of January 26, 2012


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1015 Ex Parte Reexamination Application No. 90/011,607, Request for Reconsideration filed March 26, 2012

1016 Ex Parte Reexamination Application No. 90/011,607, Declaration of Dr. Bernstein filed March 26, 2012 (including exhibits)

1017 Ex Parte Reexamination Application No. 90/011,607, Notice of Intent to Issue Ex Parte Reexamination Certificate of July 11, 2012

1018 “Thermal Conductivity of Metals,” The Engineering ToolBox, http://www.engineeringtoolbox.com/thermal-conductivity-metals-d_858.html (last visited April 1, 2015)

1019 Pierson, Handbook of Refractory Carbides and Nitrides: Properties, Characteristics, Processing, and Applications, Noyes Publications (1996)

1020 U.S. Patent No. 5,872,389 to Nishimura et al.

1021 U.S. Patent No. 5,675,174 to Nakajima

1022 U.S. Patent No. 5,538,924 to Chen

1023 U.S. Patent No. 5,300,461 to Ting

1024 U.S. Patent No. 5,729,041 to Yoo

1025 U.S. Patent No. 5,747,869 to Prall

1026 Wilson et al., Handbook of Multilevel Metallization For Integrated Circuits: Materials, Technology, and Applications, Noyes Publications (1993)

1027 Wolf, Silicon Processing for the VLSI ERA Volume 2: Process Integration, Lattice Press, Sunset CA (1990)

1028

Construction Analyses of the Samsung KM44C4000J-7 16 Megabit DRAM, published by Integrated Circuit Engineering, Scottsdale AZ, Report No. SCA 9311-3001 (available at http://smithsonianchips.si.edu/ice/cd/9311_300.pdf)

1029

Construction Analyses of the Lattice ispLSI2032-180L CPLD, published by Integrated Circuit Engineering, Scottsdale AZ, Report No. SCA 9712-573 (available at http://smithsonianchips.si.edu/ice/cd/9712_573.pdf)


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1030

Construction Analysis of the Intel Pentium Processor w/MMX, published by Integrated Circuit Engineering, Scottsdale AZ, Report No. SCA 9706-540 (available at http://smithsonianchips.si.edu/ice/cd/9706_540.pdf)

1031

“Intel Introduces The Pentium® Processor With MMX™ Technology,” http://www.intel.com/pressroom/archive/releases/1997/dp010897.htm (last visited April 14, 2015)

1032 “Intel Microprocessor Quick Reference Guide,” http://www.intel.com/pressroom/kits/quickreffam.htm#pentium (last visited April 26, 2015)

1033

Construction Analyses of the Motorola PC603R Microprocessor, published by Integrated Circuit Engineering, Scottsdale AZ, Report No. SCA 9709-551 (available at http://smithsonianchips.si.edu/ice/cd/9709_551.pdf)

1034

Construction Analyses of the Toshiba TC5165165AFT-50 64 Mbit DRAM, published by Integrated Circuit Engineering, Scottsdale AZ, Report No. SCA 9702-524 (available at http://smithsonianchips.si.edu/ice/cd/9702_524.pdf)

1035 “Material: Stainless steel, bulk,” https://www.memsnet.org/material/stainlesssteelbulk/ (last visited April 14, 2015)

1036 “Material: Silicon Dioxide (SiO2), bulk,” https://www.memsnet.org/material/silicondioxidesio2bulk/ (last visited April 14, 2015)

1037 Osaka, et al. “Development of new electrolytic and electroless gold plating processes for electronics applications,” Science and Technology of Advanced Materials, vol. 7 (2006), pp. 425-437.

1038

Uttecht et al., "A four-level-metal fully planarized interconnect technology for dense high performance logic and SRAM applications," VLSI Multilevel Interconnection Conference, 1991, Proceedings, Eighth International IEEE, June 11-12, 1991, pp. 20-26


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1039 Ex Parte Reexamination Application No. 90/011,607, Patent Owner Statement filed August 12, 2011

1040 Seshan ed., Handbook of Thin-Film Deposition Processes and Techniques: Principles, Methods, Equipment and Applications, Second Ed., Noyes Publications, New York (2002)

1041 Vlassak, et al., “A new bulge test technique for the determination of Young’s modulus and Poisson’s ratio of thin films”, J. Mater. Res., Vol. 7, No. 12, Dec 1992

1042 Ineos USA LLC v. Berry Plastics Corp., No 2014-1540, 2015 WL 1727013, (Fed. Cir. Apr. 16, 2015) (precedential)


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Micron Technology, Inc. (“Micron”) and Micron Memory Japan, Inc. (“Micron

Memory Japan” or “MMJ”) (collectively “Petitioners”) hereby petition under 35

U.S.C. §§ 311-319 and 37 C.F.R., Part 42 for Inter Partes Review (“IPR”) of claims 3-4,

6-8, 13-15, 17-18 and 21-30 (“the Challenged Claims”) of U.S. Patent No. 6,057,221

(the “’221 patent”) (Ex. 1003), filed on April 3, 1997, as reexamined pursuant to

Reexamination Request No. 90/011,607. The ’221 patent issued on May 2, 2000, to

Joseph B. Bernstein and Zhihui Duan, and is assigned to the Massachusetts Institute

of Technology (“MIT” or “Patent Owner”), according USPTO assignment records.

The Reexamination Certificate issued on September 11, 2012. There is a reasonable

likelihood that Petitioners will prevail with respect to at least one Challenged Claim.

I. MANDATORY NOTICES UNDER 37 C.F.R. § 42.8(a)(1)

A. Related Matters under 37 C.F.R. § 42.8(b)(2)

The ’221 patent is currently asserted by MIT against Micron, Micron Memory

Japan, Elpida Memory USA, Inc. (“Elpida USA”), Elpida Memory, Inc. (“EMI”)1,

and Apple Inc. in the pending litigation, MIT v. Micron Tech., Inc. et al., Civil Action No.

1:15-cv-10374, filed on February 12, 2015, in the U.S. District Court for the District

of Massachusetts.

B. Real Party-In-Interest under 37 C.F.R. § 42.8(b)(1)

Petitioners Micron and Micron Memory Japan, along with Elpida USA, Micron

1 EMI is a bankrupt Japanese entity, succeeded by and known as MMJ.


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Semiconductor Products, Inc., and the trustees reorganizing EMI in Tokyo district

court, are the real parties-in-interest.

C. Counsel and Service Information

Lead Counsel Back-Up Counsel

David J. Cooperberg (Reg. No. 63,250)

[email protected]

Kenyon & Kenyon LLP

One Broadway

New York, NY 10004

T: (212)-908-6146; F: (212)-425-5288

Thomas R. Makin ([email protected])

Rose Cordero Prey ([email protected])

Kenyon & Kenyon LLP

One Broadway

New York, NY 10004

T: (212)-425-7200; F: (212)-425-5288

Petitioners consent to email service. Back-Up Counsel will seek authorization

to submit motions to appear pro hac vice before the Board on behalf of Petitioners.

II. PAYMENT OF FEES — 37 C.F.R. § 42.103

The U.S. Patent and Trademark Office is authorized to charge the filing fee,

and any other required fees, to Deposit Account 11-0600 (Kenyon & Kenyon LLP).

III. TECHNOLOGY BACKGROUND

The ’221 patent relates to a prior-art technology commonly used in the

integrated circuit (“IC”) industry, which involves embedding fuses during

manufacturing. Ex. 1001, ¶¶ 20-22. ICs commonly include active elements (such as

transistors) formed on silicon, to which electrical connections are made using a multi-

level “interconnect” structure, each level containing electrically-conducting lines for


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interconnecting circuit elements, and each separated by an electrically insulating layer.

Id. The embedded fuses are commonly situated in one of the metal levels present in a

multi-level interconnect structure. Id.

Once an IC device containing such fuses has been fabricated, but typically

before it has been packaged, the device is tested for operability. Id. at ¶ 23-25. If

defects are detected, the fuses can be blown to disconnect the defective circuit

components and, optionally, to make alternate connections to redundant circuitry. Id.

This allows salvaging of otherwise inoperative devices, to boost overall manufacturing

yield. Id. Selectively blowing embedded fuses can also be used to program logic

devices. Id.

One common fuse structure used for repair and programming in the prior art

was the laser fuse, sometimes called a laser fuse-link, a laser cut-link, or simply a fuse-

link or cut-link. Id. at ¶ 26. To “blow” this type of fuse, a conductive element in the

IC is exposed to a focused laser beam for a length of time sufficient to evaporate or

ablate the element, thereby creating an open circuit. Id.

IV. REQUIREMENTS FOR IPR UNDER 37 C.F.R. §§ 42.104

A. Grounds for Standing Under 37 C.F.R. § 42.104(a)

Petitioners certify that the ’221 patent is available for IPR and that Petitioners

are not barred or estopped from requesting IPR.

B. Identification of Challenge Under 37 C.F.R. § 42.104(b)

Petitioners request cancellation of all Challenged Claims (claims 3-4, 6-8, 13-15,


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17-18, and 21-30—i.e., the claims that survived Ex Parte Reexamination Request No.

90/011,607), based on the following references and the Declaration of Dr. Michael

Thomas (“Thomas Declaration” or “Thomas Decl.”) (Ex. 1001):

1) Japan Pat. Appl. Publ. No. 8-213465 (“Koyou”) (Ex. 1006), published

August 20, 1996, and qualifying as prior art under 35 U.S.C. §102(a);

2) Japan Pat. Appl. Publ. No. 6-244285 (“Wada”) (Ex. 1007), published

September 2, 1994, and qualifying as prior art under 35 U.S.C. §102(b);

3) U.S. Patent No. 5,729,042 (“Lou”) (Ex. 1008), filed April 2, 1997, and

claiming priority to U.S. Patent Appl. No. 514,800 (Ex. 1009), filed

August 14, 1995, and qualifying as prior art under 35 U.S.C. § 102(e); and

4) U.S. Patent No. 5,025,300 (“Billig”) (Ex. 1010), published on June 18,

1991, and qualifying as prior art under 35 U.S.C. §102(b).

Koyou, Wada and Lou were of record during the ex parte reexamination of

the ’221 patent and formed the basis for initial rejections. Patent Owner overcame

the rejections by amendments and arguments based on an (until now) uncontroverted

declaration by patent co-inventor, Dr. Joseph Bernstein (“Bernstein Declaration” or

“Bernstein Decl.”) (Ex. 1016).

The specific statutory grounds of unpatentability are as follows:


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Ground ’221 Patent Claims Basis for Challenge

1 3-4, 6-8, 23, 25-26, 28 Anticipated under 35 U.S.C. §102(a) by

Koyou

2 14-15, 29 Obvious under §103(a) over Wada, Lou, and

General Knowledge in the Art

3 14-15, 29 Obvious under §103(a) over Wada, Billig, and

General Knowledge in the Art

4 3-4, 6-8, 23, 25-26, 28 Obvious under §103(a) over Koyou, Wada,

and General Knowledge in the Art

5 13, 17-18, 21-22, 24, 27, 30 Obvious under §103(a) over Koyou and Lou

6 13, 17-18, 21-22, 24, 27, 30 Obvious under §103(a) over Koyou and Billig

7 13, 17-18, 21-22, 24, 27, 30 Obvious under §103(a) over Koyou, Wada,

Lou, and General Knowledge in the Art

8 13, 17-18, 21-22, 24, 27, 30 Obvious under §103(a) over Koyou, Wada,

Billig, and General Knowledge in the Art

Each of these grounds is explained below and supported by the Thomas

Declaration and the other exhibits. The Thomas Declaration explains how a person

of ordinary skill in the art would have understood the scope and content of the prior

art as well as the motivation to combine the prior art teachings. The Thomas

Declaration also rebuts the Bernstein Declaration in detail.


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C. Level of Ordinary Skill in the Art

As set forth in the Thomas Declaration, a person of ordinary skill in the art

with respect to the technology described in the ’221 patent would be a person with a

Bachelor of Science degree in electrical engineering, chemical engineering, materials

science, chemistry or physics and at least 3-5 years of work experience designing

devices and/or fabricating chips, or a person with a Master’s degree in the same areas

and at least 2-3 years of the same work experience, or a person with a Ph.D. in the

same areas with 1 year of such work experience. Ex. 1001, ¶¶ 46-47.

D. Claim Construction under 37 C.F.R. §§ 42.104(b)(3)

A claim subject to IPR is given its “broadest reasonable construction in light of

the specification.” 37 C.F.R. § 42.100(b). Its terms are to be given their plain

meaning unless inconsistent with the specification. See In re Zletz, 893 F.2d 319, 321

(Fed. Cir. 1989). Petitioners submit, for this IPR, that the ’221 patent terms should be

construed to have their plain and ordinary meaning in view of the specification.

In particular, Petitioners submit that the meanings of the terms “cut-link

(cutlink) pad” (all Challenged Claims); “substrate” (all Challenged Claims); and

“harder than the substrate” (claims 14-15, 29-30) are as follows:

1) “cut-link (cutlink) pad” is “an electrically-conductive segment of a circuit capable

of being ablated in whole or in part when exposed to a laser beam”;

2) “substrate” is “base structure, including overlying insulating layers”; and

3) “harder than the substrate” is “harder than the layer of the substrate upon which


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the cut-link pad resides.”

With respect to “cut-link pad” and “cutlink pad,” the proper construction is

evident from Figures 1-11 of the ’221 patent and associated text, each depicting fuse

elements, generally labeled “20,” which are designed to be removed by laser

irradiation, and which the patent identifies as cut-link pads. See, e.g., Ex. 1003, 3:48-

4:20, 4:36-38; 6:29-31 (“When a laser pulse is incident on the cut-link pad 20, the cut-

link pad 20 is heated and expands.”), Figs. 1-11; Ex. 1001, ¶ 51.

With respect to the term “substrate,” the ’221 patent consistently defines this

term as including overlying insulating layers. See, e.g., Ex. 1003, 2:22-27 (“The

electrical interconnect of this invention includes an insulating substrate upon which a

pair of electrically-conductive lines are bonded to a cut-link pad . . .”), 6:45-57

(“Typically, the substrate 34 of a chip includes a silicon wafer base upon which a

dielectric material, such as a silicon oxide, is layered.”); see also Ex. 1005, 1306

(“substrate (1) (integrated circuits). The supporting material upon or within which an

integrated circuit is fabricated or to which an integrated circuit is attached.”); Ex.

1001, ¶ 52. Likewise, the ’221 patent consistently uses the term “harder than the

substrate” to refer to the layer of the substrate upon which the cut-link pad or fuse

resides, and not to the base substrate or wafer:

Typically, the substrate 34 of a chip includes a silicon wafer base

upon which a dielectric material, such as a silicon oxide, is layered.

The circuit is then imprinted onto the dielectric material. Because


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silicon nitride is more brittle than silicon oxide, fracture initiation is

biased toward the silicon nitride. By promoting fracture through the

passivation layer 30, rather than through the substrate 34, the metal is

more likely to be completely ablated from the chip, and the likelihood

of forming a short through the substrate is reduced.

Ex. 1003, 6:45-56; see also Ex. 1001, ¶ 53.

These constructions relating to the “substrate” are confirmed by Patent

Owner’s statements in reexamination that the Lou reference fails to provide

motivation for using a passivation layer that is “harder than the substrate”:

Lou discloses a vertical fuse structure having a pedestal 10 of silicon

oxide, resting on a layer 12 of the same material lying on the surface

of a silicon substrate 11 . . . . Although Lou discloses a fuse having a

pedestal 10 and two passivating layers 15, 16 covering the fuse, Lou is

silent as to any hardness requirements for pedestal 10 (see the Bernstein

Declaration, paragraph 73). Instead, Lou specifically discloses that

the fuse structure will still operate successfully with any material that

has relatively low thermal conductivity for the pedestal 10, without

mention of hardness. . . .

Ex. 1015, 31-32 (emphasis added)); see also Ex. 1001, ¶¶ 54-55.

V. SUMMARY OF THE ’221 PATENT

The ’221 patent, entitled “Laser-Induced Cutting of Metal Interconnect,” is

directed to methods for severing connections between electrical circuits using laser

cut-links having a particular structure. See, e.g., Ex. 1003, 1:10-21, 64-67, Figs. 3, 10;

Ex. 1001, ¶¶ 27-28. The patent explains that cut-links or fuses are commonly


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included in semiconductor circuits to allow for the bypassing of portions of circuits

that contain defects associated with the manufacturing process (see, e.g., Ex. 1003 at

1:10-14, 27-32), and discloses a cut-link consisting of a cut-link pad electrically

connected between a pair of electrically-conductive lines formed on an insulating

substrate (id. at 2:22-27). To break the cut-link and bypass portions of circuitry, a

laser is directed upon the cut-link pad until it is ablated and the conductive link

between the electrically-conductive lines is broken. Id. at 3:1-3; Ex. 1001, ¶¶ 36-38.

The ’221 patent discloses an embodiment in which the thermal resistance of

the cut-link pad is decreased, relative to co-planar connecting conductive lines, by

increasing the width of the pad relative to the connecting lines (Ex. 1003, 2:35-40,

Figs 3, 4), as well as an embodiment in which the thermal resistance of the cut-link

pad is decreased, relative to the connecting conductive lines, by constructing the pad

and lines out of materials having different thermal conductivity. Id. at 2:50-53. The

patent also discloses an embodiment in which the connecting lines extend downward

from the pad deeper into the insulating substrate to “provide a conductive link

between levels of the integrated circuit.” Id. at 8:25-30, Figs. 10-11; Ex. 1001, ¶¶ 32-

35. The patent explains that the disclosed cut-link pads can be more efficiently

ablated upon laser irradiation, because: (i) thermal energy accumulates in the pad and

is restricted (by geometry or material) from escaping through the connecting lines; (ii)

fracture toward the passivation layer is promoted through choice of materials; and (iii)

the larger pads, which more closely approximate the size of the laser beam, absorb


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more laser energy and reduce damage to surrounding material. Ex. 1003 at 3:6-30,

5:24-26, 6:13-18, 9:19-41; Ex. 1001, ¶¶ 29-30, 38.

The patent also discloses covering the pad with a passivative coating to prevent

oxidation—a technique it admits is in the prior art—and further discloses passivative

coatings comprised of a brittle material that more easily fractures and allows for

expulsion of the pad metal during ablation. Ex. 1003 at 1:16-18, 3:25-29, 6:19-21; Ex.

1001, ¶ 31.

VI. THE CHALLENGED CLAIMS

All of the Challenged Claims are directed to methods of cutting links. of

particular design, between interconnected circuits, and each claim includes a cut-link

pad “having substantially less thermal resistance per unit length” than the electrically-

conductive lines connecting to the pad. Independent claims 3, 17 and 26 are directed

to cut-link fuse geometries in which “electrically-conductive lines” make contact with

an inner, or bottom, surface of a cut-link pad and extend “from the inner surface into

the substrate.” See, e.g., Ex. 1003, Figs. 10-11, claims 3, 17, 26. Claim 3 further recites

that the cut-link pad be at least ten percent wider than the electrically-conductive

connecting lines. Claim 17 yet further recites that the pad be covered with a

passivative layer. Claim 26 recites that the pad is formed of a material having a greater

thermal conductance than the material used for the connecting lines.

Claims 4, 6-8, 13, 21-25, and 30 depend directly or indirectly from independent

claim 3. Claim 4 recites that the laser beam extends across the entirety of the cut-link


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pad. Claims 6 and 7 recite that the cut-link pad is 25% (claim 6) or 50% (claim 7)

wider than the electrically-conductive lines. Claim 8 depends from claim 7 and recites

that the pad and lines are comprised of substantially identical compositions. Claim 13

recites a passivative layer covering the pad. Claim 21 depends from claim 13 and

recites a pad comprised of material having a greater thermal conductivity than the

electrically-conductive line material. Claim 22 depends from claim 21 and recites an

aluminum pad. Claim 23 recites a pad having greater cross-sectional area than the

electrically conductive lines. Claim 24 depends from claim 13, and recites that the

passivative material layer is comprised of silicon nitride. Claim 25 depends from claim

4, and recites a cut-link pad having a length of 2-3 microns and electrically-conductive

connecting lines having a width of about 0.5 microns. Claim 30 depends from claim

13, and recites that the passivative layer is harder than the substrate.

Claim 18 depends from independent claim 17, and recites that the laser beam

extends across the entirety of the cut-link pad.

Claims 27 and 28 depend from independent claim 26. Claim 27 recites a

passivative silicon nitride layer covering the pad. Claim 28 recites an aluminum pad.

The structure recited in independent claim 14 differs from that described in the

other independent claims in that there is no limitation as to where the electrically-

conductive lines connect to the cut-link pad; therefore, it covers methods in which the

connecting lines and cut-link pad are coplanar. See, e.g., ’221 patent at Figs. 2-3. Claim

14 also recites a “passivative layer that is harder than the substrate.”


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Claim 15 depends from claim 14 and recites that the passivation layer is silicon

nitride. Claim 29 also depends from claim 14 and recites a cut-link pad width that is

at least 50% wider than the electrically-conductive connecting lines.

VII. PRIOR PROSECUTION

The ’221 patent issued on May 2, 2000. On March 30, 2011, Patent Owner

requested ex parte reexamination. Ex. 1011. Patent Owner filed a preliminary

amendment on April 14, 2011, amending certain claims, cancelling claims 1-2, 5, 9-10,

12, 16 and 20, and adding new claims 22-29. Ex. 1012. The request was granted on

June 23, 2011, Ex. 1013, and, in a non-final office action, Ex. 1014, all then-pending

claims were rejected as obvious over one or more of Koyou, Wada, and Lou. These

claims included all Challenged Claims except later-added dependent claim 30, which

recites a passivative layer harder than the substrate (as in initially rejected claim 14).

Patent Owner then submitted a declaration by named inventor Dr. Joseph

Bernstein. Ex. 1016. As explained in detail below, this declaration contains

misstatements and omissions, including: (i) failure to address the full-scope of

Koyou’s disclosure of fuse dimensions and materials, (ii) inaccurate portrayal of the

scope and content of the prior art, including accepted silicon processing methods, (iii)

inaccurate portrayal of the level of knowledge of one of ordinary skill with respect to

generally known processing technology and thin film properties, and (iv)


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inappropriate reliance on inapplicable process trends characterized in Moore’s Law.2

The examiner expressly relied on Dr. Bernstein’s deficient declaration in

subsequently allowing the Challenged Claims. Ex. 1017, 2-5.

As set forth below, Patent Owner’s Reexamination Request failed to identify—

and the examiner failed to consider—critical disclosures in Koyou which, when

properly considered, render claims 3-4, 6-8, 23, 25-26 and 28 unpatentable under §

102. These disclosure include: (i) Koyou’s disclosure of Figure 1 as a “plan view” of

Figure 3 (see Ex. 1006, Figs. 1-3, ¶¶ 0009, 0018, 0021) and (ii) Koyou’s disclosure of

titanium and titanium nitride, in addition to tungsten, for filling contact holes (Ex.

1006, ¶ 0021) so as to form electrically-conductive lines for connecting to a cut-link

pad that have thermal resistivities several times higher than those made of tungsten.

Also, as set forth in greater detail below and in the Thomas Declaration, the

examiner should not have been persuaded by Patent Owner and the Bernstein

Declaration to withdraw his obviousness rejections to the Challenged Claims.

2 Dr. Bernstein explains “Moore’s Law” as a trend identified in 1965 by Dr. Gordon

Moore “that complexity for minimum component costs has increased at a rate of

roughly a factor of two per year, and that over the longer term, there is no reason to

believe this rate will not remain nearly constant.” Ex. 1016, ¶ 40.


14

VIII. HOW THE CHALLENGED CLAIMS ARE UNPATENTABLE

A. Ground 1: Claims 3-4, 6-8, 23, 25-26 and 28 Are Anticipated Under § 102(a) by Koyou

Patent Owner failed to identify—and the examiner failed to consider—critical

disclosures within Koyou during reexamination. Considering these critical

disclosures, Koyou anticipates claims 3-4, 6-8, 23, 25-26 and 28.

1. The disclosure of Koyou

Koyou discloses IC laser fuse designs that can be cut with a relatively small

amount of energy and that minimize the damage done to regions adjacent to the fuse

member, thereby improving fuse disconnection yields and improving operational

reliability. Ex. 1006, ¶¶ 0005, 0008, 0030; Ex. 1001, ¶¶ 58-62. As with the ’221

patent, the laser fuse designs in Koyou enable the disconnection of defective circuits

and the concomitant substitution of redundant circuitry components. Ex. 1006 at ¶

0001; Ex. 1003, 1:22-25.

Figure 1(a) of Koyou (below, left) providing a “plan view” (top view) of the

fuse structure described as the “present invention” (Ex. 1006, ¶ 0009) within an

incident laser beam having spot diameter D, bears a clear resemblance to Figure 11 of

the ’221 patent (below, right) (providing a view from underneath a cut-link pad in a

multi-level via structure), as shown below:


15

Ex. 1006, Fig. 1(a)

Ex. 1003, Fig. 3

Both figures depict an elevated cut-link portion upon which laser energy is

directed (“fuse member” 1 in Fig. 1(a) of Koyou and “surface 52 of the [cut-link] pad

20” in Fig. 11 of the ’221 patent) and underlying contacts, or vias, for connecting the

fuse member, or cut-link pad, to underlying circuitry (contact regions 2a and 2b in Fig.

1(a) of Koyou and unmarked vias in Fig. 11 of the ’221 patent). Figure 1(a) of Koyou

is not referred to as an “embodiment” of the invention because it is common to all

embodiments. Ex. 1001, ¶¶ 63-66. Koyou discloses four “embodiments” in cross-

sectional view; specifically, Figures 2-5 depict alternative methods of constructing the

fuse that is presented in the “plan view” or “fundamental block diagram” in Figure

1(a). Ex. 1006, “Brief Description of Drawings” (p. 4), ¶ 0009; id. at ¶¶ 0018, 0021,

0025, 0028 (each referring to Fig. 1(a)); Ex. 1001, ¶¶ 63-66. Of particular note is the

embodiment disclosed by Koyou in Figure 3, which utilizes a “buried contact

structure” having contacts, or vias 21, fabricated of different material than fuse

member 20. Ex. 1006, ¶¶ 0019-22. The structural similarities between the cut-links


16

of Koyou and the ’221 patent are apparent as shown below in Koyou Figure 3 and

’221 patent Figure 10:

Koyou (Ex. 1006), Fig. 3

’221 patent (Ex. 1003), Fig. 10

Koyou teaches that reliability of the disclosed fuses is improved because they

are designed to better isolate the thermal energy imparted by the laser in fuse member

20 and to restrict thermal energy from propagating into the underlying circuit (see, e.g.,

Ex. 1006, ¶¶ 0018, 0022), a realization that the ’221 patent inventors mistakenly claim

as their own (Ex. 1003, 2:5-17, 3:6-12). With respect to the embodiment in Koyou

Figure 2, the thermal isolation is improved by reducing the cross-sectional area

through which contact to the underlying circuitry is made, thereby increasing thermal

resistance per unit length. See Ex. 1006, ¶ 0018; Ex. 1001, ¶¶ 67, 71-72. With respect

to the embodiment in Koyou Figure 3, this same effect is achieved by selecting a


17

material for filling fuse contacts 21 having an increased “thermal resistance”3 relative

to the fuse member 20. Ex. 1006, ¶¶ 0021-22; Ex. 1001 ¶¶ 68-70, 73.

In addition, Koyou discloses that the fuse member “is configured so as to be,

at a maximum, a size equal to the irradiation spot diameter D of the laser beam” (Ex.

1006, ¶ 0012), and that prior art fuse members extending beyond the laser

illumination region cannot be completely severed by low energy laser beams because

of the added heat capacity of the non-illuminated regions of the fuse (Id. at ¶ 0004).

2. Koyou anticipates independent claim 3

As detailed below, Koyou discloses the claimed method.

3 Koyou uses the term “thermal resistance,” which (in context) to the ordinary artisan

would have meant either, but not both: (i) an intrinsic material property (e.g., of the

material for filling contact holes), i.e., thermal resistivity, or (ii) an extrinsic quantity, i.e.,

the total thermal resistance of a structure (e.g., fuse member 20) of given material and

dimensions. Ex. 1006, ¶¶ 0017, 0020-22; Ex. 1001, ¶¶ 74-75. During reexamination,

Dr. Bernstein and Patent Owner interpreted Koyou to mean the former and

computed the relative thermal resistance per unit length disclosed by Koyou

accordingly. Ex. 1016, ¶¶ 23-26; Ex. 1015, 10-13; Ex. 1001, ¶¶ 76-77. In the

discussion to follow, Koyou will be so interpreted unless stated otherwise—even

though, for purposes of this IPR, the interpretation is of no matter. Ex. 1001, ¶ 78.


18

a. directing a laser upon an electrically-conductive cutlink pad conductively bonded between a first electrically-conductive line and a second electrically-conductive line on a substrate

During reexamination, Patent Owner acknowledged that Koyou discloses

“directing a laser upon an electrically-conductive cutlink pad conductively bonded

between a first electrically-conductive line and a second electrically-conductive line on

a substrate.” Ex. 1011, 44. Koyou discloses a laser fuse including a cut-link pad (1 in

plan view Fig. 1(a) and 20 in cross-section view Fig. 3) conductively bonded between

first and second conducting lines (2a and 2b in Fig. 1(a) and 21a and 21b in Fig. 3) on

a substrate. Koyou further discloses:

[I]n the figure, 1 indicates a fuse member (length L) that can be

broken by a laser beam; 2a and 2b indicate contact holes for

electrically connecting to the underlying wiring layers at both ends

of the fuse member 1 . . . and 5 indicates a laser beam (irradiation

spot diameter D) for breaking the fuse member 1.

Ex. 1006, ¶ 0009; see also id. at ¶¶ 0019-22. The fuse member (cut-link pad), may be

made of titanium, aluminum, titanium nitride, or polysilicon (Id. at ¶ 0016), and the

contacts may be constructed of tungsten (W), titanium (Ti) or titanium nitride (TiN)

(Id. at ¶ 0021), which are all electrically conductive. See Ex. 1001, ¶¶ 107-109.

b. the cut-link pad having substantially less thermal resistance per unit length than each of the first and second lines

During reexamination, Patent Owner acknowledged that contacts 21a and 21b

of Koyou Figure 3 teach the claimed electrically-conducting lines, but argued that fuse


19

member 20 does not have substantially less thermal resistance per unit length than

each of the first and second lines 21a and 21b. See Ex. 1011, 45, 59. Dr. Bernstein

performed a calculation purporting to show that Koyou fails to disclose this limitation

(Ex. 1016, ¶¶ 18, 22-27), upon which the examiner expressly relied (Ex. 1017, 4).

In performing his calculation, Dr. Bernstein approximated the dimensions

believed to be reasonably disclosed by Koyou, by using Koyou Figure 3 and by

assuming “state of the art” metal line-width to contact width ratios found in multi-

level interconnect circuitry at the time of Koyou’s publication. Ex. 1016, ¶ 23. In so

doing, Dr. Bernstein ignored the fuse member and contact widths shown in the plan

view in Figure 1(a) of Koyou.

Using hand-picked references allegedly setting the “state of the art” ratio of

metal line-width-to-contact width of between 13:12 and 11:10, and assuming that

Koyou’s fuses would be fabricated to have the same dimensions as these interconnect

structures, Dr. Bernstein concluded that the Figure 3 fuse member width is about

8.3%-10% greater than the contact width, contrary to what is explicitly shown in

Koyou’s Figure 1(a). Ex. 1016, ¶ 18. He further concluded that Koyou’s fuse

member thickness is 60% of the contact width, based on Figure 3. Id. at ¶ 22. From

these dimensions and the thermal conductivities Dr. Bernstein reported for aluminum

(235 W/m °K) and tungsten (170 W/m °K), Dr. Bernstein concluded that the ratio of

thermal resistance per unit length of fuse member 20 to that of contacts 21a and 21b

in Koyou is marginally greater, not “substantially less,” than that of the contacts. See id. at


20

¶¶ 18, 22-27. Calculating this ratio under Dr. Bernstein’s assumptions, including that

the Koyou fuse member has a width 10% greater than the contacts, is shown below:

( )( )( ) 10.1

1.16.01

1

fuse

contact2

fusefuse

contactcontact

contactcontact

fusefuse

contact

fuse ===

=σ

σσσ

σ

σCWCW

CWA

A

A

ARR

where R is thermal resistance per unit length, A is cross-sectional area, σ is thermal

conductivity, CW is contact width, fuse member thickness is 0.6CW, and fuse

member width is 1.1CW. Ex. 1001, ¶¶ 111-120.

However, even accepting Dr. Bernstein’s geometric estimation of the fuse

member width, which ignores the plan view shown in Figure 1(a), and which

therefore under-estimates the ratio of fuse width to contact width (for the reasons set

forth in Section VIII.A.2.c below), Dr. Bernstein’s conclusion as to this limitation is

incorrect, because his calculation assumes a fuse member formed of aluminum and

contacts formed of tungsten. Ex. 1016, ¶ 24. While Koyou does disclose this

combination of materials, Koyou also explicitly discloses that contacts 21a and 21b

can be made of other materials having thermal resistivity RTH2 “selected so as to be

higher than the thermal resist[ivity] RTH1 of the fuse member 20” such as “titanium

(Ti), titanium nitride (TiN), or the like.” Ex. 1006, ¶ 0021; Ex. 1001at ¶¶ 121-22.

The thermal resistivity of titanium, based on the same references identified by

Patent Owner during reexamination, is approximately 7.2 to 9.1 times greater than


21

that of tungsten. Ex. 1018; see also Ex 1011, 62; Ex. 1039, 16; Ex. 1001, ¶ 123.

Therefore, if Dr. Bernstein had performed his calculation using the titanium contacts

disclosed by Koyou instead of tungsten contacts, he would have inevitably concluded that

Koyou discloses a fuse member 20 (i.e., cut-link pad) having a thermal resistance per

unit length not more than 0.15 (i.e., 1.1/7.2) times, or 15%, that of contacts 21a and

21b—i.e., having “substantially less thermal resistance per unit length than each of the

first and second lines.” Ex. 1001, ¶ 124. Similarly, titanium nitride has a thermal

conductivity of 19.2 W/(m °C) (Ex. 1019, 193) or 11.1 Btu/(hr °F ft),4 and, therefore,

has a thermal resistivity 8.5 to 9.0 times greater than that of tungsten. Thus, if Dr.

Bernstein had performed his calculation using the titanium nitride contacts disclosed by Koyou

instead of tungsten contacts, he would have concluded that Koyou also explicitly discloses

a fuse member 20 (i.e., cut-link pad) having a thermal resistance per unit length not

more than 0.13 (i.e., 1.1/8.5) times, or 13%, that of contacts 21a and 21b—i.e., having

“substantially less thermal resistance per unit length than each of the first and second

lines.” Ex. 1001, ¶¶ 125-26.

Also, for completeness, if the RTH1 and RTH2 quantities associated with the fuse

member and the contact holes respectively in paragraph 22 and Figure 3 of Koyou

were interpreted to represent thermal resistance, and not thermal resistivity (see fn. 3

above), this limitation is trivially disclosed by Koyou. Under this interpretation,

4 1 Btu/(hr °F ft) = 1.731 W/(m °C). Ex. 1018; Ex. 1001, ¶ 125.


22

Koyou discloses that the thermal resistance of each filled contact hole is greater than

that of the fuse member, and, because Koyou further discloses a fuse member

substantially longer than the contact holes in Figure 3, the fuse member (i.e., cut-link

pad) has substantially less thermal resistance per unit length than each of contacts (i.e.,

the first and second lines). Ex. 1001, ¶¶ 127-28.

c. wherein the width of the cut-link pad is at least ten percent greater than the width of each of the first and second electrically-conductive lines

Koyou Figure 1(a)—a plan view of each laser fuse embodiment—discloses a

fuse wherein the “width of the cut-link pad is at least ten percent greater than the

width of each of the first and second electrically-conductive lines.” Ex. 1001, ¶ 129.

During reexamination, Patent Owner asserted that “[n]either FIG. 3 of Koyou

nor the related discussion includes any information regarding the width or cross-

sectional area of fuse and/or material in contact holes. Thus, this limitation is missing

from the reference.” Ex. 1011, 45. The Bernstein Declaration similarly concludes

that Koyou is silent with respect to the relative widths of the fuse and contact holes in

Figure 3. Ex. 1016, ¶ 17. However, they failed to credit Koyou Figure 1(a) as

providing a plan view of the “present invention” to be considered in conjunction with

Figure 3, despite their having treated Figure 3 as to-scale in concluding that the limitation

discussed in Section VIII.A.2.b above was disclosed by Koyou.

As explained in Section VIII.A.1 above, Figure 1(a) is common to all Koyou

embodiments (that are depicted in Figures 2-5). Ex. 1001, ¶ 129. Koyou Figure 3


23

shows the cross-sectional view of an embodiment in which the “buried contact”

fabrication method is used to separately deposit the contact vias 21 and the cut-link

pad 20. Ex. 1006, ¶¶ 0020-22; Ex. 1001, ¶ 129 . From Figure 1(a), then, it can be

seen that fuse member (cut-link pad) 20 of Figure 3 is at least ten percent greater in

width than the contact vias 21, (i.e., conductive lines). Ex. 1013, 8-9; Ex. 1001, ¶¶

130-34. In fact, a fuse member more than twice as wide as the contact vias is

disclosed. Ex. 1001, ¶¶ 134-39. The following annotated figures show how the two

relevant figures from Koyou relate:

Id.

Petitioners are mindful that, generally, “patent drawings do not define the

precise proportions of the elements and may not be relied on to show particular sizes

if the specification is completely silent on the issue.” Hockerson-Halberstadt, Inc. v. Avia

Grp. Int'l, Inc., 222 F.3d 951, 956 (Fed. Cir. 2000). Here, however, Koyou is not silent

as to scale. To the contrary, the fuse components are shown in relation to a circular

laser illumination spot diameter “D,” as shown in Figure 1(a). In an exemplary


24

embodiment, D “is selected to be approximately 5 µm.” Ex. 1016, ¶ 0016. Koyou

also is explicit that, as shown in Figures 1-5, the fuse member of the present invention

is proportioned “so as to be, at a maximum, a size equal to the irradiation spot

diameter D,” thereby enabling fuse disconnection using relatively low energy and less

damaging laser beams. Id. at ¶¶ 0010, 0012-13, 0016. Thus, as in Cummins-Allison

Corp. v. SBM Co., the figures in Koyou “could be dimensioned by a person having

ordinary skill in the art based on statements in the written description,” and there is

no additional requirement that the written description provide precise proportions or

particular sizes of each component shown in a figure. 484 Fed. Appx. 499, 507 (Fed.

Cir. 2012) (finding that scale and size of a figure depicting a currency counter could be

derived from a statement in the specification that it is adapted for U.S. currency).

Since Koyou expressly states that the circular beam spot in Figure 1(a) may be

5 microns, the readily ascertainable dimensions of the fuse in this embodiment

include: a fuse member length of 5 microns, a fuse member width of approximately

1.6 microns, and a contact region of approximately 0.6 microns. Ex. 1001, ¶ 139.

Koyou, therefore, discloses a fuse member, or cut-link pad, that is 167% greater in

width than that of the contacts, or conductive lines, to which it is attached. Id.

Confidence in the intended scale of Figure 1(a) is bolstered by the fact that the

’221 patent itself recognizes that contact via widths of “about a half micrometer”—

i.e., very near the 0.6 microns derived from the scale of Koyou Figure 1(a)—were

being used “in standard silicon processing” at the time. Ex. 1003, 8:32-35; Ex. 1001, ¶


25

140. The width of the fuse member computed from Koyou is also consistent with

other evidence of standard silicon processing at the time, such as was used to create

Intel’s 200MHz Pentium processor with MMX Technology. Ex. 1001, ¶ 141; see, e.g.,

Ex. 1030, 1-2, 11, Fig. 14 (showing uppermost metal 4 level having 1.5 μm (micron)

wide lines connected to underlying metal 3 level by tungsten contacts having 0.6 μm

minimum width, i.e., metal line width 150% wider than the contact width, for this

processor); Ex. 1031 (announcing a January 1997 introduction date for this

processor); Ex. 1032 (reporting an October 1996 introduction date for this processor).

Most importantly, Patent Owner and Dr. Bernstein have admitted that Koyou

Figure 3 is to scale and that one of ordinary skill in the art understood that “overlying

and underlying layers of metal must be larger and/or wider (for reasons related to

overlap, patterning and etching) than the vias.” Ex. 1015, 24; Ex. 1016, ¶¶ 22, 47; Ex.

1001, ¶¶ 142-43. In other words, processing technology generally required that cut-

link pads be at least some percentage wider than underlying vias. Ex. 1001, ¶ 144.

d. maintaining the laser upon the cut-link pad until the laser infuses sufficient energy into the cut-link pad to break the conductive link across the cut-link pad between the pair of electrically-conductive lines

In the reexamination, Patent Owner acknowledged that Koyou discloses

“maintaining the laser upon the cut-link pad until the laser infuses sufficient energy

into the cut-link pad to break the conductive link across the cut-link pad between the

pair of electrically-conductive lines.” Ex. 1011, 46. Koyou discloses a fuse member,

i.e., cut-link pad, design that may be broken or disconnected using “a laser beam with


26

a relatively low energy” to perform remedial measures using redundant circuitry. Ex.

1006, ¶¶ 0001, 0013, 0019, 0022; Ex. 1001, ¶¶ 145-46. The low energy and thermal

isolation disclosed by Koyou minimize damage to the underlying circuitry. See Ex.

1006, ¶ 0030; Ex. 1001, ¶ 147.

e. wherein the electrically-conductive cut-link pad has an inner surface facing the substrate and an opposing outer surface facing away from the substrate, the first and second electrically-conductive lines extending from the inner surface into the substrate.

In the reexamination, Patent Owner acknowledged that Koyou discloses a fuse

in which “the electrically-conductive cut-link pad has an inner surface facing the

substrate and an opposing outer surface facing away from the substrate, the first and

second electrically-conductive lines extending from the inner surface into the

substrate.” Ex. 1011, 46. Indeed, Koyou Figures 1(a) and 3 depict a cut-link pad

(labeled 1 and 20, respectively) with an inner surface facing the substrate and

electrically-conductive lines or contacts (labeled 2 and 21, respectively) extending

from the inner surface of the cut-link pad into the substrate. Ex. 1006, ¶¶ 0009, 0015,

0019-20, Figs. 1(a), 3; Ex. 1001, ¶¶ 148-49.

3. Koyou anticipates dependent claims 4, 6-8, 23 and 25

Koyou anticipates claim 4, which depends from claim 3, and recites “wherein

the laser beam extends across the entirety of the cut-link pad when the laser is

directed upon the cut-link pad.” Koyou discloses a fuse member, i.e., cut-link pad,

that is less than or equal to the size of the laser spot diameter. Ex. 1006, Figs. 1-3, ¶¶


27

0010, 0012, 0016; Ex. 1001, ¶¶ 157-58; see also Ex. 1011, 47.

Koyou anticipates claims 6 and 7, which depend from claim 3, and recite

“wherein the width of the cut-link pad is at least twenty-five percent greater than the

width of each of the first and second electrically-conductive lines” and “wherein the

width of the cut-link pad is at least fifty percent greater than the width of each of the

first and second electrically-conductive lines,” respectively. Koyou discloses a fuse

member, i.e., cut-link pad, having a width that is 167% greater than the width of its

contacts, i.e., the first and second conductive lines. See Section VIII.A.2.c above.


the cut-link pad comprises a composition substantially identical to the composition of

the first and second electrically-conductive lines.” Koyou discloses that, in addition to

the buried-contact embodiment of Figure 3, the fuse member and contacts may be

deposited concurrently using a single material, e.g., aluminum. Ex. 1006, Fig. 1(b)

(showing a single conformal deposition process for filling the contacts and forming

the fuse member), ¶¶ 0009, 0016-17 (describing a modified single deposition step with

lower step coverage); Ex. 1001, ¶¶ 161-62. Even if the fuse member and contacts

were formed of the same material, as recited in claim 8, the fuse member will have

“substantially less thermal resistance per unit length than each of the first and second

lines.” Specifically, the thermal resistance per unit length of the fuse member will be

approximately 63% (i.e., (0.60 microns contact width * 0.60 microns contact width*

100) / (1.6 microns fuse member width * 0.36 microns fuse member thickness)) that


28

of the contacts, based on dimensions derived from Figures 1(a) and (b) and using the

disclosed D=5 microns. Ex. 1001, ¶ 163.

During reexamination, Dr. Bernstein and Patent Owners argued, with respect

to Koyou Figures 1(a) and (b), that the material in contact holes 2a and 2b must be

part of the fuse member and not the conducting lines, because the material is

deposited at the same time as the fuse member. As explained by Dr. Thomas,

however, one of ordinary skill would have understood Figure 1(b) as depicting a

logical method for constructing the fuse recited in claim 8 and would have understood

contacts 2a and 2b shown in Figure 1(b) as satisfying the electrically-conductive line

limitations. Ex. 1016, ¶¶ 11, 19; Ex. 1015, 6-7, 10; Ex. 1001, ¶¶ 164-65. Claim 8 does

not require separate deposition processes, as Patent Owner suggests. Ex. 1001, ¶¶

166-67.


the cut-link pad has a greater cross-sectional area than the first and second electrically-

conductive lines, wherein the cross-sectional area of the cut-link pad is the product of

a width and a height of the cut-link pad, the first and second electrically-conductive

lines comprise vias, and the cross-sectional area of each of the first and second

electrically-conductive lines is defined by a width of the corresponding via.” As

described in Section VIII.A.2.c above, Koyou discloses a fuse member length of 5

microns and, as derived from the plan view in Figure 1(a) scaled to a 5 micron laser spot

diameter, a fuse member width of approximately 1.6 microns and a contact width of


29

approximately 0.60 microns. Ex. 1006, ¶ 0016; Ex. 1001, ¶ 169. The cross-sectional

view provided in the “buried contact” embodiment of Figure 3 likewise discloses a

fuse member thickness, for a 5 micron laser spot, of 0.36 microns. Ex. 1001, ¶ 170.

This amounts to 60% that of the contact width—the same ratio provided in the

Bernstein Declaration. See Ex. 1016, ¶ 22; Ex. 1001, ¶ 170. Based on these

dimensions, Koyou discloses a cut-link pad with cross-sectional area 60% greater than

that of its contacts, i.e., the first and second electrically-conductive lines. Ex. 1001, ¶

171.


the cut-link pad has a length of 2-3 microns, and the first and second electrically-

conductive lines each have a width of about 0.5 microns.” Koyou discloses a fuse

member where “the length L of the fuse member 10 is at most 5 µm” (which

necessarily includes a length of 2-3 microns5) and further discloses, by virtue of the

plan view of Figure 1(a) scaled by L=3 microns, contacts having a width of 0.36 microns,

5 When the prior art discloses a broader range overlapping a claimed range, it

anticipates unless the claimed range is critical to the claimed invention. Ineos USA

LLC v. Berry Plastics Corp., No 2014-1540, 2015 WL 1727013, at *4 (Fed. Cir. Apr. 16,

2015) (precedential) (Ex. 1042). There is nothing critical about the 2-3 micron range

in claim 25; the invention would operate the same way outside that range. Ex. 1001, ¶

173.


30

i.e., “about 0.5 microns.” Ex. 1006, Fig. 1(a), ¶ 0016; Ex. 1001, ¶¶ 172-73.

4. Koyou anticipates independent claim 26 and dependent claim 28

Koyou anticipates claim 26, which differs from claim 3 only in that it does not

contain a limitation as to the relative widths of the cut-link pad and conductive lines,

and instead recites “wherein the cut-link pad is formed of a material that has greater

thermal conductively [sic] than the material that forms each of the first and second

electrically-conductive lines.” As discussed in Section VIII.A.2.b above, Koyou

discloses a “buried contact” embodiment (the cross-sectional view of which is shown

in Figure 3) in which “the thermal resistance RTH2 of the material for filling the

contact holes 21a and 21b is selected so as to be higher than the thermal resist[ivity]

RTH1 of the fuse member 20,” and therefore discloses a cut-link material having

greater thermal conductivity (the inverse of resistivity) than its connecting electrically-

conductive lines. Ex. 1006, ¶ 0021; see also id. at ¶ 0017; Ex. 1001, ¶¶ 150-53. Patent

Owner acknowledged this disclosure during reexamination. Ex. 1011, 49.

Also, for completeness, if the RTH1 and RTH2 values associated with the fuse

member and the contact holes in paragraph 22 and Figure 3 of Koyou were

interpreted to represent thermal resistance and not thermal resistivity (see fn. 3 above),

this limitation is still disclosed by Koyou. Koyou discloses that the fuse member may

be made of aluminum (Ex. 1006, ¶¶ 0016, 0021-22) having a thermal conductivity

(235 W/m °K) that is greater than that of any of tungsten (170 W/m °K) (or titanium


31

or titanium nitride) which Koyou discloses as materials for filling the contact holes (id.

at ¶ 0021). See Section VIII.A.2.b above; Ex. 1001, ¶¶ 154-55.

Koyou also discloses the added limitation of claim 28, which depends from

claim 26, and recites “wherein the cut-link pad comprises aluminum.” Koyou

discloses aluminum fuse members 20. Ex. 1006, ¶¶ 0016, 0021-22 (describing a

second, alternative embodiment in which the contacts are made of materials with

higher thermal resistivity than the fuse member); Ex. 1001, ¶¶ 174-75. Patent Owner

acknowledged this disclosure during reexamination. Ex. 1039, 6.

B. Grounds 2 and 3: Claims 14-15 and 29 are Obvious under § 103(a) over Wada either in view of Lou (Ground 2) or in view Billig (Ground 3), Combined with General Knowledge in the Art

There is a reasonable likelihood that claims 14-15 and 29 are unpatentable as

obvious under 35 U.S.C. §103(a) over Wada either in view of Lou or in view of Billig.

As noted in Section VI above, independent claim 14 and dependent claims 15

and 29 do not provide any limitation as to where the electrically-conductive lines

contact the cut-link pad, and, therefore, cover methods in which the connecting lines

and fuse pad are configured in a coplanar fashion, as in Figure 3 of the ’221 patent:


32

Ex. 1003, Fig. 3.

As described in greater detail below, Wada explicitly discloses all the limitations

of claims 14-15 and 29, except a passivation layer (e.g., silicon nitride) that is harder

than a substrate layer. During reexamination, Patent Owner did not dispute that Lou

discloses laser fuses on a silicon dioxide substrate and covered with a silicon nitride

passivation layer, or that silicon nitride is harder than silicon dioxide. Ex. 1011, 52-54;

Ex. 1016, ¶¶ 74-75; Ex. 1015, 31-32. Thus, during reexamination, these claims were

initially rejected over the combination of Wada and Lou. Ex. 1014, 11. The examiner

ultimately withdrew these rejections based on factually incorrect statements made by

Dr. Bernstein in paragraphs 73-78 of his declaration. See Ex. 1017, 4-5. As detailed

below, the combination of Wada, the general knowledge in the art, and either Lou or

Billig, discloses all of the limitations of claims 14-15 and 29, and renders these claims

unpatentable under §103(a).

1. The disclosure of Wada

Wada, like the ’221 patent, discloses a design for a laser fuse, referred to as a

“redundancy fuse,” for use in repairing ICs. Ex. 1007, Abstract, ¶ 0002. According

to Wada, “[a] redundancy fuse is used for switching from a circuit in which a failure

has occurred to a redundant circuit.” Id. at ¶ 0002. Also, like the ’221 patent, Wada

discloses a fuse pad portion, or “melting portion,” of the fuse (i.e., a cut-link pad), that

is within a laser irradiation region and wider than the conducting lines, or “non-

melting portions,” connecting to the cut-link pad. Id. at ¶¶ 0002, 0010, 0013. Wada


33

Figures 1 and 2, shown below, disclose representative embodiments depicting melting

portions6 1a and 5a, respectively.

Id. at Figs. 1-2.

Wada also discloses that the connecting lines (1b and 6 in Figs. 1 and 2,

respectively) are dimensioned so as to have higher thermal resistance, thus reducing

the “escape of heat generated in the melting portion” of the fuse device during laser

irradiation. Id. at ¶¶ 0009, 0014-15; Ex. 1001, ¶¶ 82-85, 88. The melting portions

disclosed by Wada are within the laser radiation region and are designed to occupy “as

close as possible to the area” of the laser irradiation beam so as to reduce the amount

of laser irradiation that “leaks to under-layers” of the circuit. Ex. 1007, ¶ 0012; ¶¶

6 When the “melting portions” are “melted,” the “redundancy fuse” is “broken,” and

the circuit is disconnected. See Ex. 1007, ¶ 0002 (“[T]his is adapted so that the normal

circuit operates if the redundancy fuse is not broken and the redundant circuit

operates if it is broken. The redundancy fuse is generally melted by focusing

irradiation of an energy beam such as a YAG laser.”); Ex. 1001, ¶¶ 83-84.


34

0007-8, 0010 (further disclosing a rectangular fuse portion, or cut-link pad, of 2

micron width within a laser irradiation region 3 microns in diameter)7; Figs. 1-2.

Wada summarizes various advantages associated with thermal isolation of the

irradiated fuse portions, and with sizing these irradiated portions to absorb as much

laser energy as possible:

[T]he energy of the energy beam can be also lowered [relative to]

that which was conventional. Furthermore, this also has an effect

in that the amount of laser light that irradiates the periphery of the

melting portion and leaks to under-layers can be made less than

was conventional, and thus heat damage to an element present in

a layer below the redundancy fuse or a substrate can be reduced;

and moreover this also has the effect of reducing the amount of

transmitted heat as compared to that which was conventional, and

consequently reducing adverse effects of heat on circuit devices

connected to the redundancy fuse and the wire.

Id. at ¶ 0018; see also id. at ¶¶ 0006, 0012, 0015; Ex. 1001, ¶¶ 86-87.

2. The disclosure of Lou

Lou, like Wada, discloses a laser fuse structure, referred to as a “fusible link”

for use in repairing defects in underlying ICs. Ex. 1008, Abstract, 1:13-26, 2:48-52;

7 The largest fuse pad that can fit entirely within a beam spot 3 micron in diameter

has a width of 2.12 (i.e., 3/sqrt(2)) microns, thus confirming that the disclosed 2

micron pad is within the beam spot. Ex. 1001, ¶ 86.


35

Ex. 1009, 5-6, 9, 20.8 A representative embodiment is shown below:

Ex. 1008, Fig. 2 (cross-sectional view, showing a two layer fusible link 13 and 14); see

also id. at 3:29-39; Ex. 1009, 11-12, 23.

Lou further discloses the fusible link is fabricated on insulating silicon oxide

layers 10 and 12,9 and an uppermost passivation layer 16 of silicon nitride covers the

fuse. Ex. 1008, 3:14-16, 49-59; Ex. 1009, 11-13. The silicon oxide layer may be

silicon dioxide. Ex. 1008, 2:14-18; Ex. 1009, 8. A threshold laser energy was

determined for fracturing the passivation layers and vaporizing fuse links constructed

as shown in Figure 2. Ex. 1008, 4:22-24, 29-33, 44-49; Ex. 1009, 14-15. Lou explains

8 Petitioners provide parallel citations to Lou (Ex. 1008) and to the August 14, 1995

application (Ex. 1009) to which it claims priority, in order to establish that Lou’s

effective 102(e) date is August 14, 1995. Petitioners have added page numbers to Ex.

1009 for ease of reference.

9 In Figure 2 of Lou, labels 12 and 15 point to the same layer, but the text makes clear

to one of ordinary skill in the art that 12 should refer to the film underlying fuse link

pedestal 10. Ex. 1008, 3:10-28; Ex. 1009, 11; Ex. 1001, ¶¶ 91-92.


36

that raising the fusible link 13 and 14 off the silicon substrate 11 advantageously

provides “a measure of thermal isolation for the fuse when it is irradiated by the

laser.” Ex. 1008, 2:61-65, 3:10-19, 4:50-53; Ex. 1009, 10-11, 15.

3. The disclosure of Billig

Billig Figure 3 (below) discloses a laser blowable fusible link 14, which may be

made of aluminum, and protective layer 30, both formed on a silicon dioxide

insulating substrate 13 that may be flowable glass, spin-on glass, or silicon dioxide

deposited by, e.g., tetraethoxysilane (TEOS) precursor gas. Ex. 1010, Figs. 2-4, 2:25-

30, 2:36-41, 3:33-41; Ex. 1001, ¶ 100.

Billig discloses that the protective layer 30 “helps prevent contaminants from

reaching the active device areas on the integrated circuit substrate” and “helps protect

the integrated circuit from scratches,” i.e., that the protective layer is a passivation

layer. Ex. 1010, 5:8-15; Ex. 1001, ¶¶ 101-02. Billig further discloses that this layer

may be made of silicon nitride. Ex. 1010, 4:58-61; Ex. 1001, ¶ 103.

4. Wada and either of Lou or Billig, combined with general knowledge in the art, disclose every limitation of claim 14

As detailed below, Wada and either of Lou or Billig, combined with general

knowledge in the art, disclose the claimed method.


37

a. directing a laser upon an electrically-conductive cut-link pad conductively bonded between a first electrically-conductive line and a second electrically-conductive line on a substrate

During reexamination, Patent Owner acknowledged that Wada discloses

“directing a laser upon an electrically-conductive cutlink pad conductively bonded

between a first electrically-conductive line and a second electrically-conductive line on

a substrate.” Ex. 1011, 40. Wada discloses a laser fuse having a “melting portion,”

i.e., a cut-link pad, (1a in Fig. 1 and 5a in Fig. 2 shown in Section VIII.B.1 above) that

is within a laser irradiation region (4 in both Figs. 1 and 2) conductively bonded

between first and second conducting lines on a substrate (1b in Fig. 1 and 6 in Fig. 2).

See, e.g., Ex. 1007, ¶¶ 0010, 0013-14, Figs. 1-2; Ex. 1001, ¶ 182.

b. the cut-link pad having substantially less thermal resistance per unit length than each of the first and second lines

During reexamination, Patent Owner did not dispute that Wada discloses “the

cut-link pad having substantially less thermal resistance per unit length than each of

the first and second lines.” See, e.g., Ex. 1011, 40-41. The fuse structures disclosed by

Wada meet this limitation because Wada discloses, explicitly or in view of the general

knowledge in the art, a fuse structure made of a single material and having a melting

portion (cut-link pad), having a larger cross-sectional area than the non-melting line

portions to which the cut-link pad is connected.

In particular, Wada discloses a first laser fuse embodiment in Figure 1 having

non-melting connecting lines 1b that are 50% as wide as the irradiated fuse (cut-link


38

pad) portion 1a. Ex. 1007, ¶ 0010, Fig. 1; Ex. 1001, ¶¶ 185-86. Wada also discloses a

second laser fuse embodiment in Figure 2, again having non-melting connecting lines

6 that are 50% as wide as the irradiated fuse, or cut-link pad, portion 5a. Ex. 1007, ¶

0013, Fig. 2. Wada also discloses that the melting and non-melting portions of the

fuse are formed of the same material. See Ex. 1007, ¶ 0010; Ex. 1001, ¶ 187. Further,

because fabricating cut-links with a constant thickness was routine, and because

constructing otherwise would have required added processing expense, one of

ordinary skill in the art would have understood (as Dr. Bernstein and Patent Owner

did) Wada as disclosing melting and non-melting portions deposited in a single step

thereby having the same film thickness, or would at least have considered a single

thickness construction to be a routine and natural design choice. Bernstein Decl.(Ex.

1016), ¶ 35 (“[T]he fuse structures disclosed in Wada are horizontal structures, in

which the fuse pad (i.e., the ‘fusing portion’) and the first and second electrically-

conductive lines (i.e., the ‘non-fusing portions’) are formed at the same time from the

same material in the same layer of metallization.”), ¶ 36 (“In horizontal fuse

structures, one dimension is constant (i.e., the thickness of the fuse pad and the

conductive lines is the same).”); Ex. 1015, 16-17; Ex. 1001, ¶ 187; see also Ex. 1020,

Figs. 3-4, 3:62-65; Ex. 1021, Figs. 7A-7B, 6:62-7:18; Ex. 1006, Figs. 6(a)-(b).

Because the melting portion (cut-link pad) and non-melting connecting lines

are made of the same material and have the same thickness, and because the fuse

portion (cut-link pad) has cross-sectional width 100% larger than that of the non-


39

melting connecting lines, the cross-sectional area (the product of width and thickness)

of the melting portion is also 100% larger than that of the non-melting connecting

lines and “the cut-link pad ha[s] substantially less thermal resistance per unit length

than each of the first and second lines.” Ex. 1007, ¶¶ 0010, 0013, Figs. 1-2; Ex. 1001,

¶¶ 188-90. Wada is clear on this point, stating that a “region having high thermal

resistance is provided in a portion of the non-melting portions,” and accordingly,

“escape of heat generated in the melting portion can be reduced.” Ex. 1007, ¶ 0009.

c. wherein the cut-link pad is covered with a passivative layer that is harder than the substrate

As explained in Section VIII.B above, during reexamination, Patent Owner did

not dispute that Lou discloses laser fuses on a silicon dioxide substrate that are

covered with a silicon nitride passivation layer, or that silicon nitride is harder than

silicon dioxide.10 The ’221 patent itself acknowledges that silicon nitride layers are

harder than silicon oxide layers (Ex. 1003, 2:59-67), and, in fact, this is so where 10 While Lou uses the general term “silicon oxide” in the preferred embodiments,

Lou confirms that laser fusible links may be formed more particularly over “silicon

dioxide” in the “background.” Ex. 1008, 2:14-18; Ex. 1009, 8; see also Ex. 1015, 30

(“Lou discloses . . . silicon dioxide . . . .”); Ex. 1016, ¶¶ 73-76; Ex. 1001, ¶ 191. The

term “silicon oxide” was well-known to broadly encompass a family of silicon dioxide

(SiO2) based insulating materials. See, e.g., Ex. 1010, 3:47-49 (referring to “oxide”),

4:58-60 (referring to same layer as silicon “dioxide”); Ex. 1001, ¶ 191.


40

conventional deposition techniques are chosen—an obvious design choice. (Ex.

1001, 192, 195-98). Therefore, Lou’s disclosure of a silicon nitride layer over a silicon

oxide (and silicon dioxide) substrate, and general knowledge, meet this limitation.

Alternatively, Billig discloses use of a silicon nitride passivation layer overlying a

laser cut-link for protection against contamination and scratching. Ex. 1010, 4:58-61;

5:8-15; Ex. 1001, ¶ 193. Billig also discloses a SiO2 layer, e.g., deposited with TEOS,

underlying the cut-links, which is softer than conventional silicon nitride passivation

layers resulting from common processes. Ex. 1010, 2:25-30; Ex. 1001, ¶¶ 193-98.

d. maintaining the laser upon the cut-link pad until the laser infuses sufficient energy into the cut-link pad to break the conductive link across the cut-link pad between the pair of electrically-conductive lines

During reexamination, Patent Owner did not contest that Wada discloses

“maintaining the laser upon the cut-link pad until the laser infuses sufficient energy

into the cut-link pad to break the conductive link across the cut-link pad between the

pair of electrically-conductive lines.” Ex. 1011, 41. The process disclosed by Wada

for disconnecting redundancy fuses, whereby a melting portion (or cut-link pad) is

irradiated and removed by an energetic laser beam as needed to activate redundant

circuitry, meets this limitation. Ex. 1007, ¶¶ 0002 (“[T]his is adapted so that the

normal circuit operates if the redundancy fuse is not broken and the redundant circuit

operates if it is broken. The redundancy fuse is generally melted by focusing

irradiation of an energy beam such as a YAG laser.”), 0007, Figs. 1-2; Ex. 1001, ¶¶

199-200.


41

5. Wada and either of Lou or Billig, combined with general knowledge in the art, disclose every limitation of dependent claims 15 and 29

Wada, either of Lou or Billig, and the general knowledge in the art, disclose

every limitation of claim 15, which depends from claim 14, and recites “wherein the

passivation layer comprises silicon nitride.” As explained in Section VIII.B.4 above,

Wada, either of Lou or Billig, and the general knowledge in the art, disclose every

limitation of claim 14; and, as explained in Sections VIII.B.2 and 3 above, Lou and

Billig each disclose the silicon nitride passivation layer recited in claim 15.

Wada, either of Lou or Billig, and the general knowledge in the art, disclose

every limitation of claim 29, which depends from claim 14, and recites “wherein the

width of the cut-link pad is at least fifty percent greater than the width of each of the

first and second electrically-conductive lines.” As explained in Section VIII.B.4

above, Wada, either of Lou or Billig, and the general knowledge in the art, disclose

every limitation of claim 14; and, as explained in Section VIII.B.4.b above, Wada

discloses silicon redundancy fuses having fuse, or cut-link pad, portions (1a in Fig. 1

and 5a in Fig. 2) that are 100% wider than non-melting electrically-conductive lines

connected at either end of the irradiated fuse pad portion (1b in Fig. 1 and 6 in Fig. 2).

Ex. 1007, ¶¶ 0010, 0013, Figs. 1-2; Ex. 1001, ¶ 205.


42

6. A person of ordinary skill in the art would have been motivated to combine the teachings of Wada, either of Lou or Billig, and the general knowledge in the art, thereby rendering claims 14, 15 and 29 obvious

As explained in Sections VIII.B.4 and 5 above, Wada’s fuses, alone or in

combination with the general knowledge in the art, disclose every limitation of claims

14, 15 and 29, except for a passivation layer (e.g., silicon nitride) covering the cut-link

pad that is harder than the substrate layer beneath the cut-link pad. Also, as explained

in Sections VIII.B.2, 3 and 4.c above, Lou and Billig each disclose a silicon nitride

passivation layer over a laser fuse link formed on a silicon dioxide substrate, which,

with the general knowledge, meets these limitations. Contrary to Dr. Bernstein’s

assertions, incorporating these teachings into Wada would have been obvious.

As an initial matter, silicon nitride was commonly used as a passivation layer to

prevent corrosion and contamination of laser fuse pads and upper metal layers of ICs.

For example, the ’221 patent acknowledges that laser cut-links were regularly coated

with upper passivation layers (Ex. 1003, 1:16-20), and Lou and Billig each disclose an

uppermost passivation layer of silicon nitride covering a laser fuse pad (Ex. 1008,

3:49-59; Ex. 1009, 12-13; Ex. 1010, 5:8-15, 4:58-61) that remains intact until fractured

during laser illumination and vaporization of an underlying fuse11 (Ex. 1008, 4:21-28,

44-49; Ex. 1009, 14-15; Ex. 1010, 1:63-65, Fig. 4). In addition, the prior art contains 11 This is important because the claims require the passivation layer to exist at the

time the laser is “direct[ed] upon” the cut-link pad.


43

many references employing these techniques. For example, U.S. Patent No. 5,872,389

(“Nishimura”) discloses laser fuses on silicon oxide substrate layers that are covered

by a silicon nitride layer through which laser radiation is applied. Ex. 1020, 4:33-35,

8:20-24, Figs. 1, 3-6; see also Ex. 1021, Figs. 2, 7A (fuse 43 and passivation layer 24),

7b, 9, 4:11-18 (protective silicon nitride layer 24 over fuse wiring 22 on insulating

substrate 20 in Fig. 2), 4:62-5:12 (explaining the importance of laser illumination with

the passivation layer intact), 6:62-7:18 (fuse wiring 43 covered by silicon nitride

passivation layer 24); Ex. 1022, Figs. 3-4 (fuse 28 and a passivation layer 38 on a

dielectric substrate 20 and 22), 2:44-59 (described fuse structures help prevent

contamination/moisture), 4:39-52 (TEOS and BPSG silicon oxide substrate layers 20

and 22), 4:7-8 (laser illumination region 42), 5:13-17 (metal fuse 28), 5:66-6:3

(passivation layer 38 preferably made of silicon nitride); Ex. 1001, ¶¶ 208-212.

More broadly, silicon nitride was routinely used as an upper passivating layer

for protecting ICs. Ex. 1001, ¶ 213. For example, U.S. Patent No. 5,300,461 (“Ting”)

teaches that silicon nitride has unique strengths as a passivation layer material. Ex.

1023, Fig. 5, 2:21-36 (describing superior barrier protective properties of silicon

nitride), 8:36-43, 8:63-33; see also Ex. 1024, Fig. 6, 3:57-67, 6:11-27; Ex. 1026, 259-262

(noting that silicon nitride layers are used “extensively” for passivation). In addition,

the ICE reports cited by Patent Owner during reexamination indicate the use of an

upper most silicon nitride passivation layer. See Ex. 1028, 10, Fig. 34; Ex. 1029, 2.

Further, silicon dioxide insulator layers were, and still are, pervasively used as the


44

inter-level insulators on which metal interconnect circuitry is fabricated. See, e.g., Ex.

1027, 194-199; Ex. 1026, 202-205, 243-59; Ex. 1001, ¶ 214.

Because metal fuse links and upper metal levels, which can include metal fuse

links (see, e.g., Ex. 1006, Figs. 4-5), were commonly encapsulated in passivative silicon

nitride layers, and because metal interconnect circuitry (including fuses) were routinely

fabricated on silicon dioxide insulating layers, it would have been a routine design

choice to combine Wada, either of Lou or Billig, and the general knowledge in the art

to render unpatentable claims 14, 15 and 29 of the ’221 patent. Ex. 1001, ¶ 215.

7. Patent Owner’s reexamination arguments do not overcome unpatentability over Wada, either of Lou or Billig, and the general knowledge in the art

As noted above, during reexamination, Patent Owner did not dispute that Lou

discloses silicon nitride passivating layers overlying laser fuse links, or that Lou

discloses underlying substrate layers of silicon dioxide. Ex. 1015, 31-32; Ex. 1008,

2:14-20, 3:10-22, 48-59; Ex. 1009, 8, 11-13. Patent Owner also did not dispute that

silicon nitride is harder than silicon dioxide. Ex. 1015, 31-32; Section VIII.B above.

Patent Owner merely criticized Lou for not “requiring” the use of silicon nitride. Ex.

1015, 32. However, obviousness references are not disqualified merely because they

do not suggest that a particular combination is the preferred combination. See In re

Fulton, 391 F.3d 1195, 1200 (Fed. Cir. 2004). Lou, with general deposition knowledge,

discloses laser fuse links with a silicon nitride passivative layer that is harder than an

underlying silicon dioxide substrate layer, meeting the passivative layer limitations of


45

claims 14, 15, and 29. Whether or not Lou requires this combination, or expressly

discusses film hardness, does not alter the fact that the combination of Wada, Lou and

general knowledge would have been obvious.

Patent Owner further argued during reexamination, based on Dr. Bernstein’s

declaration, that persons of ordinary skill would not have incorporate the teachings of

Lou into Wada, because “the accepted wisdom is that covering an object with a

relatively hard material makes it more difficult to break,” and, therefore, one would

not have thought to use a passivating layer that is harder than the substrate. See Ex.

1016 ¶¶ 77-79. The examiner expressly withdrew objections over Wada in view of

Lou in response to this assertion. Ex. 1017, 4-5. However, the Bernstein Declaration

is contradicted by the facts.

First, as noted above, the prior art (e.g., Lou, Billig, Nishimura and Chen)

teaches the use of silicon nitride passivation layers overlying laser fuse links formed

on softer silicon dioxide substrate layers, exactly as claimed. Ex. 1001, 218-221.

Second, Dr. Bernstein improperly equates hardness with resistance to fracture. Ex.

1001, ¶¶ 222-25. But, a skilled artisan would have known that harder materials are

often more brittle and more susceptible to fracture. Id. Even lay persons understand

that glass is considerably more susceptible to fracture than stainless steel or gold, yet

glass is the hardest of these materials. Compare Ex. 1036 (glass hardness of 710-790

Knoop (Kg/mm2), with Ex. 1035 (stainless steel hardness of 660 Knoop (Kg/mm2)),

Ex. 1037, 434 (gold plating hardness of 170-200 Knoop (Kg/mm2); Ex. 1001, ¶ 224.


46

One of ordinary skill in the art would not have been discouraged from using silicon

nitride as a fuse link passivation layer in combination with a silicon dioxide underlayer,

based on the fact that silicon nitride is conventionally the harder material, as the cited

prior art confirms. Ex. 1001, ¶ 225.

Last, commonly used silicon nitride passivation layers were known to have high

mechanical stress when deposited and to be susceptible to cracking as thickness

increased or during subsequent heating. Ex. 1027, 273-74. This is further evidence

that persons of ordinary skill in the art did not consider silicon nitride films harder to

fracture than silicon oxide films as Dr. Bernstein asserted. Ex. 1001, ¶¶ 226-27.

C. Ground 4: Claims 3-4, 6-8, 23, 25-26 and 28 are Obvious under § 103(a) over Koyou in View of Wada, Combined with General Knowledge in the Art

Even if it were determined that Koyou (i) does not disclose a cut-link pad

having a width 10%, 25%, or 50% wider than the width of electrically conducting

lines connected to the pad (independent claim 3 and dependent claims 6-7), (ii) does

not disclose the relative thickness of the cut-link pad, such that the thermal resistance

per unit length of the cut-link pad relative to the conductive lines (all independent

claims) can be determined,12 and/or (iii) does not disclose a cut-link pad having a

12 In order to determine the ratio of thermal resistances per unit length, one must

determine the ratio of the cross-sectional area of the cut-link pad to that of the

conductive lines. Ex. 1001, ¶ 229.


47

length of 2-3 microns and electrically-conductive lines having a width of about 0.5

microns (claim 25), claims 3-4, 6-8, 23, 25-26, and 28 are still unpatentable as obvious

under 35 U.S.C. §103(a) in view of Koyou, Wada and general knowledge in the art.

Based on the prior reexamination of the ’221 patent, Petitioners anticipate the

disclosure of these limitations being significant issues in this IPR. The motivation to

combine the teachings of Koyou and Wada also is likely to be a significant issue (see

infra Section VIII.C.3). Therefore, Petitioners submit that Grounds 1 and 4 are not

redundant of each other and request institution of IPR on both.

1. Koyou and Wada, combined with general knowledge in the art, disclose every limitation of claims 3-4, 6-8, 23, 25-26, and 28

With respect to the limitations reciting a cut-link pad having 10%, 25%, and

50% greater width than that of the electrically-conductive lines, Wada discloses

multiple laser fuse embodiments containing a laser cut-link pad having a width 100%

greater than the width of the electrically-conductive lines that contact the fuse pad.

See Ex. 1007, Figs. 1-3, ¶¶ 0010 (disclosing line 1b as 1 micron wide and pad 1a as 2

microns wide), ¶ 0013; see also Section VIII.B.4.b above; Ex. 1001, ¶ 230.

With respect to cut-link pad thickness, one of ordinary skill in the art, as

acknowledged in the Bernstein Declaration, wishing to construct the buried contact

laser fuses disclosed in Koyou would have naturally employed well-known multi-level

interconnect fabrication methods at the time. Ex. 1016, ¶¶ 23-25, 47; see also Ex.

1001, ¶ 231. This is unsurprising because (i) Koyou explicitly discloses embodiments


48

in which the laser fuse is situated at upper metal levels (see Ex. 1006, Figs. 4-5) and (ii)

positioning laser fuses in upper metal levels was generally known in the art (see, e.g.,

Ex. 1038, Fig. 4; Ex. 1021, Fig. 9, 8:34-49; Ex. 1010, Figs. 1-4, 2:36-43). Ex. 1001, ¶

232. Reliance on conventional upper metal level fabrication techniques would also

have been obvious because adopting established processes for contact and film

deposition avoids cost associated with implementing special processing steps. Ex.

1006, Abstract, ¶¶ 0008, 0030;Ex. 1001, ¶ 233.

Standard buried contact interconnect processing at the time of filing of the ’221

patent yielded metal interconnect levels (i.e., the levels within which the cut-link pad

would be embedded) with thicknesses ranging from about 87.5%-145% that of the

underlying contact (via) widths. See, e.g., Ex. 1030, 11-12 (0.55 micron wide vias

extending from the bottom of M3 interconnects having a thickness of 0.8 microns);

Ex. 1033, 11-12 (0.7 micron wide vias extending from the bottom of M5

interconnects having a thickness of 0.73 microns); Ex. 1034, 14-15 (0.4 micron wide

vias extending from the bottom of M2 interconnects having a thickness of 0.46

microns); Ex. 1038, Tables 1-2, Figs. 2-4 (1.2 micron wide vias extending from the

bottom of a laser link fuse constructed in M3 having a thickness of 1.05 microns); Ex.

1001, ¶ 234. The cited ICE reports provide representative examples of the same “half

micron technology” that the ’221 patent describes as being “used in standard silicon

processing” and recommends for use in constructing the fuses recited in independent

claims 3 and 26. Ex. 1003, 8:32-35; Ex. 1001, ¶ 235.


49

Using this standard technology, even if one of ordinary skill were to construct

the fuses of Koyou using fuse thicknesses at the bottom end of the 87.5%-145% range

given above, the combination of Koyou and Wada (which teaches cut-link pad width

200% that of contact width) would yield fuse pads having cross-sectional area 175%

(i.e., 200%*0.875) that of the contacts, easily meeting the limitation recited in claim 23.

Ex. 1001, ¶ 236. Furthermore, with this ratio of cross-sectional areas, choosing a cut-

link pad material of aluminum and a contact material of tungsten, as taught by Koyou

(see Section VIII.A.2.b above) and commonly employed at the time (see id. at ¶ 237),

and using the thermal resistivity data utilized by Dr. Bernstein (Ex. 1016, ¶ 24), the

ratio of cut-link pad thermal resistance per unit length to electrically-conducting line

thermal resistance per unit length is computed to be:

41.075.1R

R

fuse

contact

fusefuse

contactcontact

contact

fuse ===σ

σσσ

AA

Ex. 1001, ¶ 237. In other words, “the cut-link pad [has] substantially less thermal

resistance per unit length than each of the first and second lines,” as recited in

independent claims 3 and 26. Id. at 238. Also, as discussed in Section VIII.A.2.b

above, Koyou’s Figure 3 and associated text disclose this limitation trivially if

understood to be referencing thermal resistance and not thermal resistivitiy. Ex. 1001, ¶¶

239-40.

With respect to claim 25, which depends from claim 4, and recites “wherein the

cut-link pad has a length of 2-3 microns, and the first and second electrically-


50

conductive lines each have a width of about 0.5 microns,” even if this limitation is not

disclosed by Koyou as set forth in Section VII.A.3 above, the disclosure in Koyou and

Wada combined with the general knowledge in the field would have rendered claim 25

obvious. Koyou discloses a laser beam diameter of approximately 5 microns and a

fuse member, or cut-link pad, with a length of “at most 5 µm” (which necessarily

includes a length of 2-3 microns). Ex. 1006, ¶ 0016; Ex. 1001, ¶ 242. Wada discloses

a laser beam diameter of 3 microns and a melting portion (cut-link pad) that fits

within the beam and has length 2 microns, which is “a length of 2-3 microns.” Ex.

1007, ¶ 0010; Ex. 1001, ¶ 243. Wada also discloses first and second electrically

conductive lines having a width of 0.5 microns. Ex. 1007, ¶ 0013, Fig. 2. In addition,

the ’221 patent itself recognizes that contact via widths of “about a half micrometer”

were used “in standard silicon processing” at the time. Ex. 1003, 8:32-35; see also

Ex.1030, 1-2, 11, Fig. 14 (showing uppermost metal 4 level having 1.5 μm wide lines

connected to underlying metal 3 level by tungsten contacts having 0.6 μm minimum

width). Therefore, the claimed 0.5 micron electrically-conductive line width is either

disclosed by Wada or represents an obvious design choice. Ex. 1001, ¶¶ 245-46.

2. Motivation to combine Koyou, Wada, and the general knowledge in the field is found in the references themselves and in the general prior art

Koyou and Wada each provide motivation for the proposed combination.

Koyou and Wada are directed to laser fuses used to repair defective ICs. As noted

Sections VIII.A.1 and B.1 above, both references recognize the importance of


51

preventing excess heating of underlying circuitry by minimizing heat transfer out of an

irradiated cut-link fuse. Both further recognize that this thermal isolation can be

achieved by making connections to the pad using lines or contact vias having

increased thermal resistance. See Sections VIII.A.2.b and B.4.b above.

For example, Koyou discloses that the thermal resistivity of lines contacting the

fuse member should be increased, “thus making it difficult for the heat that is

produced in the fuse member 10 by the laser beam . . . to propagate to the wiring

layers.” See Ex. 1006, ¶¶ 0018, 0021, 0022; Ex. 1001, ¶¶ 249-50. Similarly, Wada

teaches that wider fuse pads with lower thermal resistance per unit length provide

desirable thermal isolation, efficient energy use, and less radiation leakage to

peripheral regions. See Ex. 1007, ¶¶ 0009-14; Ex. 1001, ¶ 251. Koyou also

emphasizes the importance of improving the success rate for severing targeted laser

cut-links. Ex. 1006, ¶ 0002 (“[T]he ratio at which the laser fuses can be successfully

broken (that is, break yield) has a large impact on the product yield . . . .”); Ex. 1001,

¶¶ 287-90 (rebutting Dr. Bernstein’s assertion that the relation between break yield

and product yield was “surprising”). Last, Koyou discloses a cut-link pad “a size equal

to the irradiation spot diameter D of the laser beam” (Ex. 1006, ¶ 0012), and Wada

teaches that making the illuminated pad portion of the fuse commensurate in size

with the laser beam spot reduces damage caused by laser irradiation of underlying

circuitry (Ex. 1007, ¶ 0012; id. at ¶¶ 0007-8, 10). Ex. 1001, ¶ 252.


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Additional motivation to combine can be found in Nishimura, which discloses

laser fuses with cut-link pads wider than connecting lines and observes that wider fuse

pads are more easily and reliably blown. Ex. 1020, Figs. 3-4, 5:46-56; Ex. 1001, ¶ 253.

For all of the above reasons, it would have been obvious to adapt the fuse

member disclosed by Koyou to meet the limitations of claims 3-4, 6-8, 23, 25-26, and

28. In particular, it would have been obvious to one of ordinary skill in the art to

increase the width of the fuse member in Koyou relative to the width of the contacts

serving as the claimed electrically-conducting lines. Both Koyou and Wada teach the

benefits arising from the concomitant improvement in the thermal isolation of the

fuse from the underlying circuitry, and Wada further teaches that a wider fuse

member would have the added benefit of reducing undesirable irradiation of

underlying circuitry. Ex. 1001, ¶¶ 254-56.

3. Patent Owner’s reexamination arguments do not overcome unpatentability over Koyou and Wada

Claims 3-4, 6-8, 23, 25-26, and 28 were initially rejected over the combination

of Koyou and Wada during reexamination. Ex. 1014, 4. Patent Owner relied on the

Bernstein Declaration in responding, and the examiner cited it as “instrumental” in his

decision to ultimately withdraw his initial rejections. See Ex. 1017, 2-4. As detailed

below, Dr. Bernstein materially misstated the disclosure of the prior art in his

declaration. Without these inaccuracies, claims 3-4, 6-8, 23, 25-26 and 28 are obvious

over Koyou in view of Wada, as the examiner initially concluded.


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a. One of ordinary skill in the art would not have preferred increases in cut-link pad thickness as an alternative to increasing cut-link pad width

During reexamination, Patent Owner argued, relying on the Bernstein

Declaration, that one of ordinary skill in the art would not have been motivated to

increase the width of the “vertical” fuse in Koyou by following Wada’s teachings

relating to “horizontal” fuses because, in contrast to horizontal fuses, the thickness of

the fuse pad and connecting lines in “vertical fuses” (i.e., the contacts) are

independent, thereby permitting the fuse-pad area to be increased relative to

connecting line area by varying the fuse pad thickness instead of its width. Ex. 1016

¶¶ 36-37; Ex. 1015, 16-18.

However, this argument contradicts the conventional wisdom of one of

ordinary skill in the art at the time the ’221 patent was filed. Increasing fuse pad

thickness beyond that used to deposit the metal interconnect level containing the laser

fuse would have required the development of new processing steps and would have required

that the fuse pads be fabricated independently from other metal levels, thus increasing

the number of processing steps required, all of which would have been contrary to the

conventional desire to minimize processing and process development to increase

product yield. Ex. 1001, ¶¶ 262-63. This conventional wisdom is confirmed by

Koyou, which explicitly states that a benefit of its disclosed laser fuse embodiments is

that additional manufacturing processes are not needed. Ex. 1006, Abstract, ¶¶ 0008, 0030.

Since increased yield and reduced cost are critical to IC manufacturers, one of


54

ordinary skill in the art would have opted to increase cut-link pad width, as taught by

Wada, rather than increase its thickness as Dr. Bernstein suggested. Ex. 1001, ¶ 264.

Moreover, Dr. Bernstein admitted that one of ordinary skill in the art would

not have looked to increasing film thickness to reduce thermal resistivity per unit

length because such increases would increase the heat capacity of the fuse and,

consequently, would increase the energy of the laser illumination required to blow the

fuse. Ex. 1016, ¶¶ 43-45; Ex. 1015, 22-23. Since increased laser energy risks increased

damage to surrounding circuitry (Ex. 1006, ¶ 0005; Ex. 1007, ¶¶ 0012, 0018), one of

ordinary skill would have opted to increase pad width rather than pad thickness to

reduce the pad’s thermal resistance, as taught by Wada. Ex. 1001, ¶¶ 265-66.

Dr. Bernstein also opined that increasing fuse width would not have been

obvious because it would “increase the probability that some part of the fuse member

20 may not receive sufficient energy for complete fuse ablation.” Ex. 1016, ¶ 41.

This observation ignores the fact that both Koyou and Wada teach fuse pads that are

purposefully sized to be within the laser beam spot. Ex. 1006, Figs. 1-5, ¶¶ 0010, 0016;

Ex. 1007, Figs. 1-2, ¶¶ 0010. Koyou and Wada additionally disclose laser beam spots

in the range of 3 to 5 microns in diameter, far in excess of the approximately 0.5

micron contact width that is suggested by the ’221 patent, is disclosed by Koyou, and

was industry-standard. Ex. 1006, ¶ 0016; Ex. 1007, ¶ 0010. As a consequence, cut-

link pad widths 50% (or more) wider than contact widths, as taught by Wada, could


55

easily have been fabricated without the risk, as perceived by Dr. Bernstein, that the

pad would extend beyond the illumination region. Ex. 1001, ¶¶ 269-71.

b. Moore’s law would not have posed an impediment to the combination of Koyou and Wada

During reexamination, Dr. Bernstein opined that Moore’s law demands ever-

increasing circuit density that would have taught away from increasing the size of fuse

widths beyond 10% that of underlying contacts. Ex. 1016, ¶ 40; see also Ex. 1015, 19-

20. The examiner relied on these opinions in concluding that the combination of

Wada and Koyou was not obvious. Ex. 1017, 4. Dr. Bernstein’s reasoning is

demonstrably flawed. Increasing the width of the fuse pad so as to be commensurate

in size with the illumination region does not conflict with Moore’s Law.

First, since Koyou teaches that laser fuses may be located in upper metal levels

(Ex. 1006, Figs. 3-5; see also Ex. 1038, Fig. 4), the pressure of minimized feature size

associated with Moore’s law generally does not apply. Ex. 1001, ¶¶ 275-80. It is well-

known that, generally, the geometric constraints imposed by Moore’s law become

more relaxed for interconnect levels that are further removed from the active devices

of the circuit, i.e., the transistors and/or memory cells. Id. Higher levels of a

multilevel interconnect contain fewer circuit elements, ultimately culminating in a level

having only a comparatively small number of contact pad structures of size far in

excess of the minimum dimensions used at the transistor level of the device. Id.

Laser fuse pads in these upper metal levels simply are not constrained such that their


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width cannot be increased. Id.

Second, persons skilled in the art understood that fuse pads needed to be

spaced at least a laser beam’s diameter apart. Id. at 281. Wada teaches increasing cut-

link pad widths such that the pads are up to, but not exceeding, the size of the laser

beam exposure area. Ex. 1007, Figs. 1-2, ¶¶ 0010, 0013. Consequently, Wada cannot

be in tension with Moore’s Law, regardless of the width of the fuse pad, since typically

no other circuits can be located within the beam diameter. Ex. 1001, ¶ 282.

One of ordinary skill in the art would have recognized that Moore’s Law was

inapplicable, as explained above. For example, U.S. 5,747,869 (“Prall”) states:

Most components of the memory devices can be scaled to meet the

space restrictions resulting from the higher densities. However,

laser fuses used to implement redundancy cannot be scaled due to

mechanical restrictions related to current laser technology. Fuse

width must be kept large enough to cover the laser spot so that the

fuse can absorb a large quantity of heat. In addition, the fuse-to-

fuse space must be kept large enough to allow for mechanical laser

alignment tolerances and to prevent unintentional programming of

a fuse adjacent to an exploding fuse.

Ex. 1025, 1:57-67.

With this recognition that laser fuses cannot be scaled to dimensions smaller

than the laser beam diameter, and the fact that Wada, Koyou and the ’221 patent

disclose (i) the use of well-known half-micron silicon processing where contacts or

vias, i.e., electrically-conducting lines, are approximately half of a micron wide, and


57

(ii) representative laser spot diameters of approximately 3 microns (Ex. 1007, ¶ 0003),

approximately 5 microns (Ex. 1006, ¶ 0016), and “about two microns” (Ex. 1003, 5:6-

7), one of ordinary skill in the art would have seen no impediment to constructing

cut-link pads having widths 50% (or more) than the contact width. Ex. 1001, ¶ 284.

Increased pad widths, which have the known benefits explained in Section VIII.C.3

above, would remain safely within the illumination region commonly used for laser

cutting. Ex. 1001, ¶ 285.

Third, interconnect line widths substantially larger than contact widths were

being used in mass-produced ICs at the time, for example, in Intel’s Pentium

processor. See Ex. 1030, 1-2, 11, Fig. 14 (showing metal 4 level having 1.5 μm wide

lines connected to underlying metal 3 level by contacts having 0.6 μm minimum

width, i.e., metal line width 150% wider than the contact width); Ex. 1001, ¶ 286.

Consequently, Dr. Bernstein’s appeal to Moore’s Law was unfounded and incorrect.

D. Grounds 5 and 6: Claims 13, 17-18, 21-22, 24, 27, and 30 are Obvious under § 103(a) over Koyou either in view of Lou (Ground 5) or in view of Billig (Ground 6)

Claims 13, 17-18, 21-22, 24, 27, and 30 are unpatentable as obvious under 35

U.S.C. §103(a) over Koyou in view of either Lou or Billig. Claims 13, 21-22, 24, and

30 depend directly or indirectly from independent claim 3; claim 18 depends from

independent claim 17; and claim 27 depends from independent claim 26. Koyou

meets all the limitations of independent claims 3 and 26 for the reasons provided in

Sections VIII.A.2 and 4 above. Further, for the reasons provided in Section VIII.A.2


58

above, Koyou alone discloses all the limitations of claim 17 except “a passivative layer

covers the cut-link pad” (claim 17 being otherwise identical to claim 3).

Koyou discloses the added limitation of claim 18, which depends from

independent claim 17, and recites “wherein the laser beam extends across the entirety

of the cut-link pad when the laser is directed upon the cut-link pad,” as explained in

Section VIII.A.3 above with respect to claim 4.

Koyou discloses the added limitation of claim 21, which depends from claim

13, and recites “wherein the cut-link pad comprises a material with greater thermal

conductivity than the material comprising each of the first and second electrically-

conductive lines,” as set forth above in Section VIII.A.4 regarding claim 26.

Koyou discloses the added limitation of claim 22, which depends from claim

21, and recites “wherein the cut-link pad comprises aluminum,” as explained in

Section VII.A.4 above with respect to claim 28.

Claims 13 and 17 recite “a passivative layer cover[ing] the cut-link pad”; claim

24 and 27 recite a silicon nitride “passivative layer”; and claim 30 recites a “passivative

layer [that] is harder than the substrate.” As explained in Section VIII.B above, Patent

Owners have admitted that silicon nitride is harder than silicon dioxide, and the use of

silicon nitride passivation layers for protecting underlying laser fuses on softer silicon

dioxide insulating layers is disclosed by both Lou and Billig, and general knowledge

and represented a known design choice for fabricating ICs. See Section VIII.B above.

Because Koyou, like Wada, is directed toward laser fuses, and because Koyou


59

further discloses laser fuses encompassed in insulating materials, the motivation for

combining Koyou with either Lou or Billig is the same as that for combining Wada

with either Lou or Billig, and is set forth in Section VIII.B.6 above. Ex. 1001, ¶ 299.

Further, the ’221 patent acknowledges that passivation layers for covering fuse pads

were well known and well understood at the time. Ex. 1003, 1:16-20; Ex. 1001, ¶ 300.

E. Grounds 7 and 8: Claims 13, 17-18, 21-22, 24, 27, and 30 are Obvious under § 103(a) over Koyou in view of Wada and in further view of either Lou (Ground 7) or Billig (Ground 8), Combined with General Knowledge in the Art

Claims 13, 17-18, 21-22, 24, 27, and 30 are unpatentable under 35 U.S.C.

§103(a) over Koyou in view of Wada and in further view of either Lou or Billig,

combined with general knowledge in the art. Claims 13, 21-22, 24, and 30 depend

directly or indirectly from independent claim 3, claim 18 depends from independent

claim 17, and claim 27 depends from independent claim 26. Koyou and Wada meet

all the limitations of independent claims 3 and 26 for the reasons provided in Sections

VIII.A.2, A.4 and C.1 above. For these same reasons, Koyou and Wada disclose all

the limitations of claim 17 except “a passivative layer covers the cut-link pad.”

As explained in Section VIII.D above, claims 13 and 17 recite “a passivative

layer cover[ing] the cut-link pad”; claim 24 and 27 recite a silicon nitride “passivative

layer”; and claim 30 recites a “passivative layer [that] is harder than the substrate.”

Dependent claims 18, 21 and 22 recite additional limitations which are

disclosed by Koyou, as explained in Section VIII.D above.


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As explained in Section VIII.B above, Patent Owners have admitted that

silicon nitride is harder than silicon dioxide, and the use of silicon nitride passivation

layers for protecting underlying laser fuses on softer silicon dioxide insulating layers is

disclosed by both Lou and Billig, and general knowledge and represented a known

design choice for fabricating ICs. See Section VIII.B above.

The motivation for combing Koyou and Wada is provided in Section VIII.C.2

above. Because Koyou and Wada are directed toward laser fuses, and because Koyou

further discloses laser fuses encompassed in insulating materials, the motivation for

further combining Koyou and Wada with either Lou or Billig is the same as that for

combining Wada with either Lou or Billig, and is set forth in Section VIII.B.6 above.

Ex. 1001, ¶ 307. Further, the ’221 patent acknowledges that the use of passivation

layers for covering fuse pads was well-known and well-understood at the time. Ex.

1003, 1:16-20; Ex. 1001, ¶ 308.

IX. CONCLUSION

Petitioners respectfully request institution of inter partes review of the ’221

patent. In view of the foregoing reasons, the prior art references either alone or in

combination, as specified in Grounds 1-8 of this petition, establish a reasonable

likelihood of success that claims 3-4, 6-8, 13-15, 17-18, and 21-30 are unpatentable.

Respectfully submitted,

/s/ David J. Cooperberg___

David J. Cooperberg Reg. No. 63,250


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Lead Counsel for Petitioners

David J. Cooperberg Thomas Makin Rose Cordero Prey Kenyon & Kenyon LLP One Broadway New York, NY 10004 Telephone: 212.425.7200 Facsimile: 212.425.5288

Certificate of Service

The undersigned hereby confirms that the foregoing Inter Partes Review

Petition, along with associated Exhibits 1001 through 1042, was served on May 4,

2015, via FedEx upon the following:

Andrew Fortney Central California IP Group, P.C. 410 W. Fallbrook Avenue #211 Fresno, CA 93711

(phone) (559-840-0841) with courtesy copies served on:

Massachusetts Institute of Technology 77 Massachusetts Avenue Cambridge, Massachusetts 02139

Ramzi R Khazen McKool Smith, P.C. 300 W. 6th Street Suite 1700 Austin, TX 78701

/s/ David J. Cooperberg .

David J. Cooperberg Kenyon & Kenyon LLP One Broadway New York, NY 10004-1007 Tel: 212-425-7200

inter partes - fish & richardson’s post-grant practice · 2017-04-22 · 1:15-cv-10374, filed...

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