ir-obirch analysis system -1000 · ±10 mv to ±10 v 100 ma 1 na*1 fixed current type ±10 mv to...

IR-OBIRCH analysis system

-1000 R

2

When the interconnect line through which the current is flowing is irradiated by an IR laser beam, the heat gener-ated causes the resistance to increase, which in turn re-duces the current. In an OBIRCH image, this is displayed as a dark area. (See the above right photo.)If a void or defect exists in the line, heat conduction in the affec-ted area is changed in comparison to the normal areas, such that the temperature is different. These areas of change can be highlighted in the OBIRCH image.Areas displayed as bright on the OBIRCH image have a neg-ative temperature coefficient of resistance (TCR) for the material comprising these areas, indicating that the heat generated by the IR laser beam has caused the current to increase.

Objective lens: NIR 100×Voltage: 4.8 VCurrent: 1 mA

▲ Refractive image (Backside observation)

Current Line

▲ OBIRCH image

Current Path

I ( R/V)I2

T, TCR

I

Laser (front side)

Laser (backside)

Si-sub.

A1

A1

*Depends on defects and materials

Defects in Metal Line

Leakage Current Path

Heated

Laser : = 1.3 μm

I : Current before laser irradiation

TCR : Temperature coefficient of resistance

I : Current change due to laser irradiation (when constant voltage is applied)

R : Resistance increase with the temperature increase due to laser irradiationT : Temperature increase due to laser irradiation

V : Applied voltage

orV

or

V= R × I

V : Voltage change due to laser irradiation (when constant current is applied)OBIRCH signal

I

● Localization of leakage current path• IDDQ failure analysis

● Detection of metal defect• Inspection of defect in the metal line (void, Si module)• Inspection of abnormal resistance part at contact hole (via contact)• Metallization process monitoring

* IDDQ (Quiescent power supply current): IDDQ is the quiescent power supply current that flows after the MOS transistor switching is complete.

PRINCIPLE OF OBIRCH ANALYSIS

● High spatial resolution image

● Backside observation (λ=1.3 μm)

● Observation of highly doped substrate (Epi-sub.)

● Using an infrared laser (wavelength: 1.3 μm) means that no OBIC signal is produced in the semiconductor field, which enables the OBIRCH signal caused by the defect to be detected.

● Possible to measure at 4 quadrant voltage/current

● Up gradable to emission microscope (option)

Artificial shortages Artificial shortages

*

IR-OBIRCH Analysis System

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The μAMOS is a semiconductor failure analysis system which uses the IR-OBIRCH method for localization of leakage current paths and the abnormal resistance points in LSI devices.

Main applications Features

Objective lens: NIR 100×

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Measurement examples

▲ IR-OBIRCH imageThe leakage current path is displayed in dark contrast and the defect location is displayed in bright contrast.

▲ Observation result under high magnification(IR-OBIRCH superimposed image)The bright contrast was detected between the AI lines.

▲ Cross-sectional TEM image of defect locationShort circuit exists due to remaining barrier metal.

IR-OBIRCH image (Superimposed)Interconnect where current is flowing (sections where the OBIRCH signal has decreased) are displayed in green, and shorted locations (sections where the OBIRCH signal has increased) are displayed in red.

▲

▲ Objective lens: NIR 5×Voltage: 4.8 VCurrent: 1 mA

Data supplied by Renesas Technology Corporation.

Data supplied by Renesas TechnologyCorporation.

DRAM, Vdd-GND leakage current failure analysis

IDDQ failure analysis

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Data courtesy of Dr.P. Jacob(EMPA in Switzerland)



▲ IR-OBIRCH image (Superimposed)

▲ IR-OBIRCH image (Superimposed)

▲ IR-OBIRCH image (Superimposed) ▲ Cross-sectional SEM image of defect location

▲ Cross-sectional SEM image of defect location

▲ Cross-sectional SEM image of defect location

Measurement examples

Contact failure: Via contact areas have high resistance Detection of a faulty contact among a number of contacts

Short circuit between lines: Short circuit due to remaining polymer Example of short circuit due to remaining polymer between the first and second layers

Function failure: Void in lines Identification example of defect location causing function failure in an LSI chip The location where a void exists in the lines has been detected.

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• Optical stage travel range*

Selectable among 3 modes: fixed voltage mode, fixed current mode,

and microcurrent amplifier (fixed current type) mode, which are

controlled by the software.

*1 Minimum detectable pulse signal input into the amplifier*2 Calculated value

Applied voltage

Max. current

Detectability

Fixed voltage type

±10 mV to ±10 V

100 mA

1 nA*1

Fixed current type

±10 mV to ±10 V

100 mA

1 μV*2

Microcurrent amplifier

±10 mV to ±25 V

100 μA

3 pA*1

X

Y

Z

±20 mm

±20 mm

75 mm

* These values may become smaller due to interference with the prober used and the sample stage.

* 2 lenses can be selected among * marked lenses.

** With glass thickness compensation function

1× : A7649-012× : A8009M-PLAN-NIR-5× : A11315-01M-PLAN-NIR-20× : A11315-03M-PLAN-NIR-50× : A11315-04NIR 50× : A8756-01High NA50× : A8018M-PLAN-NIR-100× : A11315-05NIR 100× : A8756-02M-PLAN-NIR-100×HR : A11315-06G-PLAN-APO-NIR-100× HR : A11315-08

μAMOS-1000

0.030.0550.140.400.420.420.760.500.500.700.70

20 34

37.5 20 17

18.3 12 12

13.3 10 6

Numerical aperture

WD (mm)

Lens

Standard

The newly developed OBIRCH amp A8755-06 has the 3 times better

sensitivity and the ability to cancel noise from external equipment

such as a tester.

without noise cancel with noise cancel

Former amp

Line profile Line profile

New amp

**

* **

** **

**

13×13 6.5×6.5 2.6×2.6

0.65×0.650.26×0.26 0.26×0.26 0.26×0.26 0.13×0.13 0.13×0.13 0.13×0.13 0.13×0.13

Up to 5 lenses selectable for a turret

Improve internal circuit noise of amp itself <3 times better S/N than the former amp>

Integrate noise cancellation function <by improving noise caused by external equipment>

Noise Noise

Field ofview

IR confocal laser scan microscope

Reflected images and OBIRCH images are obtained, and then both images are superimposed.

• Laser*

512 × 512

1024 × 1024

Scan speed (second/image)

1

2

2

4

4

8

8

16

Output: 100 mW

Output: 400 mW or more

Output: 200 mW (CW), 800 mW (pulse)

* For 1.3 μm laser, one of two laser can be integrated.

The IR confocal laser scan microscope obtains clear, high-contrast

pattern images by scanning the backside of a chip with the infrared

laser. Within 1 second a pattern image can be acquired. By the

flexible scan in 4 directions, it is possible to scan a device from

different directions without rotating it. Scanning in parallel with a

metal line makes OBIRCH image clearer. The function is also useful

in OBIRCH analysis using a digital lock-in and soft defect localization

by laser illumination.

1.3 μm Laser diode

1.3 μm High power laser (option)

1.1 μm Laser diode (option)

< Standard function >Dual scan: Obtain a pattern image and an IR-OBIRCH image simultaneously

Flexible scan: Normal scan (1024 × 1024, 512 × 512), Zoom, Slit scan, Area scan, Line scan, Point scan, Scan direction changeable (0°,45°,90°,180°,270°)

Lens magnification

Obtaining OBIRCH images

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Optional

OptionalOptionalOptional

OptionalOptionalOptional

New OBIRCH amp. can work for devices, which need to apply

negative voltage/current. The new amp is also effective to detect

reverse current flowed differently from design.

Possible to measure at 4 quadrant voltage/current

Sink Source+25 V

-25 V

+10 V

-10 V

+100 μA +100 mA-100 μA-100 mA

Positive voltage/Negative current

Negative voltage/Positive current

Analysis is within a possible range

SinkSource

Positive voltage/Positive current

Negative voltage/Negative current


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The M10383 digital lock-in kit is a new function added to the OBIRCH analysis, in order to boost detection sensitivity by sampling one pixel into multiple data using lock-in processing. The M10383 allows acquiring a sharp and clear image in a short acquisition time compared to the A9188-01 lock-in kit which uses an analog processing method.

▲ Backside observationsHigh resolution is achieved using the correction function for the glass thickness and Si substrate thickness.

NIR100× (NA0.5) High NA, 50× (NA: 0.76) Correction ring 0.4

▲ OBIRCH observationsHigh sensitivity is achieved with a high numerical aperture (NA).

NIR100×, 20 mV (1.74 mA) High NA50×, 20 mV (1.74 mA)

This lens was specifically designed for infrared observations of wavelengths 1 μm or greater. Laser light-gathering efficiency is increased and pattern image resolution is improved with OBIRCH detection sensitivity and high magnification.

• Si substrate thickness correction function: 0 μm to 700 μm • Glass thickness correction function: 0 mm/2 mm switching

• Evaluation results of high NA 50× objective lens(comparison of high NA 50× objective lens with M plan NIR 100× lens)

Time domain analysisIn digital lock-in, the modulation cycle is divided by the number of samplings. Changes in an image over time can be shown (motion image display is possible) by constructing sliced images using this same subdivided tim-ing data. This helps easily identify defect points based on the delay in the IR-OBIRCH signal. This technique is shown in the figure below, using TEG (test element group) metal as an example. Here the time domain analysis by digital lock-in shows that foreign contamination in the metal react more slowly to laser heat emission than other sections of metal.

Number of samplings per cycle (32 data)

Creatingsliced images



Creating sliced images from the same subdivided timing data

Digital lock-in sliced images

Standard lens principles

Laser spot

Totalreflection Back side

Pattern sideSmall N.A.

Si

NanoLens principles

Laser spot

Back side

Pattern sideLarge N.A.

Emissions

Si

Laser lightcollection

NanoLens

Objective lens Objective lens

A8018 High NA 50× objective lens

Improvement

For backside observation, near-infrared light is used to penetrate the Si layer. On the other hand, optical resolution gets worse at longer wavelengths. The NanoLens (a solid immersion lens) is a hemispherical lens that touches the LSI substrate and utilizes the index of refraction of silicon to increase the numerical aperture, which improves spatial resolution and convergence efficiency. By setting the NanoLens on a point to observe on the backside of a device, it is possible to perform analysis at a sub-micron level of spatial resolution in a short period of time with greatly improved accuracy.

NanoLens (solid immersion lens) C9710

Digital lock-in kit M10383

Analysis using the current detection head

Current detection head

Applicable voltage

Applicable current

Detectability

Standard type*1

Max. 250 V

6.3 A (Max. 10 A)

High voltage type (optional)

3 kV

30 mA(90 VA)

A current detection head can be used to measure devices that require higher voltage or higher current than the range of standard OBIRCH amp (10V/100 mA or 25V/100 μA).

*1 The standard type head is included in M10383 Digital Lock-in kit.*2 Minimum detectable pulse signal input into an OBIRCH amp. Detectability can differ by device set-up environment.

10 nA*2

Digital lock-in (5 kHz, 52 s)Analog lock-in (5 kHz, 72 s)

Comparing analog lock-in with digital lock-in (short scan period)

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Change from Fail to Pass

Data Courtesy ofMr. Seigo Ito (Fujitsu Corporation)

For an SRAM that becomes defective over 4 V at VDD, DALS

analysis was carried out. The Pass/Fail changes were detected due

to laser heat at three locations. Failure mechanism was further

investigated with one signal.

A change from Fail to Pass was indicated in a transistor of the timing

circuit. A delay generated in the transistor switching turns the device

into normal operation (Pass). Including the results of the

investigations done on the other two locations, the cause was

defined as insufficient timing margin between the sense amplifier

signal and the word line signal. The problem was fixed by slowing

the sense amplifier signal timing and speeding up the word line

signal timing.

Change from Fail to

Pass due to a delay

caused by laser.

(

(

)

)

Fail

Pass

Fail(abnormal)(normal)Pass

Analysis of an SRAM having insufficient voltage margin

This is windowing function with dynamic analysis by laser stimulation.

Full flexible scan function

Number of windows

Window size *1

Window position

Scan direction *2

Pixel rate *2

Multi area scan

0°, 45°, 90°, 180°, 270°

128 μs/pixel to 128,000 μs/pixel

Laser scan mask

-

-

*1 : Multiple number of 16 *2 : Pixel rate is changeable by each window

3 scan areas & 1 mask area

Detect DALS signal in each window

No laser scanon laser mask area

Multi area scanPossible to set multiple windows to scan only specific areas. Window can be set at any number, size, scan speed and direction in the list below. This function makes measurement time much shorter instead of standard scanning to observe whole view size.

Laser scan maskPossible to set masks on areas where laser illumination changes device behavior in order to prevent you don't want or unexpected change.

Max. 30

16 to 512 pixels in each X and Y direction

Any location within the field of view

Dynamic analysis by laser stimulation kit (DALS) A9771

Due to high integration and increased performance of LSI, functional failure analysis under LSI tester connection becomes very important. Dynamic analysis by laser stimulation (DALS) is a new method to analyze device operation conditions by means of laser radiation. Stimulate a device with a 1.3 μm laser while operating it with test patterns by LSI tester. Then device operation status (pass/fail) changes due to heat generated by the laser. The pass/fail signal change is expressed as an image that indicates the point causing timing delay, marginal defect, etc.

Analysis done by driving an LSI under conditions at the boundary

* The Pass/Fail status changes as a reaction to the laser stimulation

Pass/Fail mapcorresponding to laser scan

Imageformation

Pass/Fail status

LSI tester

Failure location

Status changes due tolaser heat

Change in status in reaction to the laser = failure location

Concept of the analysis of a failed device by utilizing the "drive voltage – operating frequency" characteristics

Failure location information can be easily transferred to another analytical instrument by marking the area of an identified failure location, or by marking around it.

The laser marker uses a pulse laser, and its spot size is φ5 μm under a 100× lens.

Laser marker C7638

Sequence software

This function enables automatic measurement of IR-OBIRCH observation by following the procedure set by a user. IR-OBIRCH images can be sequentially measured and saved by combining with a semi-automatic prober. Measurements under the condition with an LSI tester or an external power source are possible as well.

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EO Probing Unit C12323-01

The EO Probing Unit is a tool to observe a transistor's status through the Si substrate using an incoherent light source. It is composed of the EOP (Electro Optical Probing) to measure operation voltage of a transistor rapidly and the EOFM (Electro Optical Frequency Mapping) to image active transistors at a specific frequency.

T6,T7,T8 react to the laser.


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Cat. No. SSMS0004E10JAN/2014 HPKCreated in Japan

Hamamatsu Photonics c lassi f ies laser diodes, and provides appropriate safety measures and labels according to the classification as required for manufacturers according to IEC 60825-1. When using this product, follow all safety measures according to the IEC. Caution Label

LASER SAFETY

CLASS Ι LASER PRODUCT

Description Label (Sample)

★ μAMOS are registered trademark of Hamamatsu Photonics K.K. (France, Germany, Italy, Japan, U.K., U.S.A.) ★ Product and software package names noted in this documentation are trademarks or registered trademarks of their respective manufacturers.• Information furnished by HAMAMATSU is believed to be reliable. However, no responsibility is assumed for possible inaccuracies or omissions.

Specifications and external appearance are subject to change without notice.© 2014 Hamamatsu Photonics K.K.

Utility

Dimensions/Weight (Including option)

Wafer* Diced chip to 300 mm wafer

200/300 mm wafer (other sizes can be handled with the available options)

Packaged IC

IC that opened to the chip surface

IC that mirror polished to the Si substrate

Front

Backside

* According to the specifications of the prober used

μAMOS main unit

μAMOS control rack

PC desk

Dimensions/Weight

(W) 1360 mm × (D) 1410 mm × (H) 2120 mm, Approx. 900 kg



Line voltage

Power consumption

Vacuum

Compressed air

AC 220 V (50 Hz/60 Hz)

3000 VA

Approx. 80 kPa or more (Using prober)

0.5 Mpa to 0.7 Mpa

Front

Backside

LSI tester

Connector boardAdapter board

Connector panel

Coaxial cable

Internalpowersource

OBIRCH amplifier

Tester / OBIRCH switching

GND

Vdd

Signal

When performing problem analysis of complicated LSI chips on a large scale, it is possible to connect through a navigation software (Magma Camelot, Schlumberger Limited, and Advantest Corporation). This helps the study of the causes of problem locations by superimposing defect signals or images over the layout diagram. In addition, the optical system of μAMOS-1000 can be controlled externally using the CAD-navigation software.

* Analysis cannot be performed during dynamic action. The signal will be fixed in a poor state and analyzed.

Example of connecting to a μAMOS tester

Because the IR-OBIRCH amplifier is equipped with a function to automatically switch between internal and external power sour-ces, IR-OBIRCH analysis can be performed when connected to an LSI tester by inserting the OBIRCH amplifier in the connection cables between the LSI tester head and the device (adapter board) as shown in the figure.

Applicable device

CAD navigation

Tester connection / IR-OBIRCH analysis

Combining detection signals from μAMOS-1000 and design data, and automatically extracting suspicious signal lines contributes to making the work of narrowing down the malfunction locations more effective and to reducing the time needed to clarify the route cause. Analysis is easily possible using GDS ll only at both laboratory and office.

Pattern images / Design information

Design information overlay/Automatical signal region setting

Automatic NET extraction

NET highlight display

Acquires a superimposed the signal image and the pattern image provided by failure analysis system.

Design data (CAD data) can also be superimposed on a failure analysis image. Allows signal region parameter setting.

Automatically extracts the NET passing through sig-nal regions. Ranks the NETs in order of most num-ber of times they pass through the signal region.

This function highlights a specified NET from among the extracted NETs. Analyzing this NET assists in identifying the failure location in a short time.

CAD Data

Wiring informationlogic information

Failure localization supported by FA-Navigation

Failure informationphysical analysis information

Integrated Information

μAMOS-1000

Connection with the FA-Navigation failure analysis support system

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HAMAMATSU PHOTONICS K.K.HAMAMATSU PHOTONICS K.K., Systems Division812 Joko-cho, Higashi-ku, Hamamatsu City, 431-3196, Japan, Telephone: (81)53-431-0124, Fax: (81)53-435-1574, E-mail: [email protected].: Hamamatsu Corporation: 360 Foothill Road, Bridgewater. N.J. 08807-0910, U.S.A., Telephone: (1)908-231-0960, Fax: (1)908-231-1218 E-mail: [email protected]: Hamamatsu Photonics Deutschland GmbH: Arzbergerstr. 10, D-82211 Herrsching am Ammersee, Germany, Telephone: (49)8152-375-0, Fax: (49)8152-2658 E-mail: [email protected]: Hamamatsu Photonics France S.A.R.L.: 19, Rue du Saule Trapu, Parc du Moulin de Massy, 91882 Massy Cedex, France, Telephone: (33)1 69 53 71 00, Fax: (33)1 69 53 71 10 E-mail: [email protected] Kingdom: Hamamatsu Photonics UK Limited: 2 Howard Court, 10 Tewin Road, Welwyn Garden City, Hertfordshire AL7 1BW, United Kingdom, Telephone: (44)1707-294888, Fax: (44)1707-325777 E-mail: [email protected] Europe: Hamamatsu Photonics Norden AB: Torshamnsgatan 35 SE-164 40 Kista, Sweden, Telephone: (46)8-509-031-00, Fax: (46)8-509-031-01 E-mail: [email protected]: Hamamatsu Photonics Italia S.r.l.: Strada della Moia, 1 int. 6, 20020 Arese (Milano), Italy, Telephone: (39)02-93581733, Fax: (39)02-93581741 E-mail: [email protected]: Hamamatsu Photonics (China) Co., Ltd.: B1201 Jiaming Center, No.27 Dongsanhuan Beilu, Chaoyang District, Beijing 100020, China, Telephone: (86)10-6586-6006, Fax: (86)10-6586-2866 E-mail: [email protected]

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ir-obirch analysis system -1000 · ±10 mv to ±10 v 100 ma 1 na*1 fixed current type ±10 mv to...

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