challenges of ald/cvd precursor development

Progress and Challenges of

ALD/CVD Precursor Development

Wonyong Koh

linkedin.com/in/wonyong-koh-5652844

https://www.linkedin.com/in/wonyong-koh-5652844





Korea CGMG Workshop 2017

Agenda

• Brief History of CVD/ALD

Metal-Organic Precursors

• Precursor Development Challenges:

Business Model Problem

• Summary


Disclaimer

• The opinions expressed in this presentation and

on the following slides are solely those of the

presenter.


Metal-Organic CVD Precursor R&D In ‘90s


Cu CVD Precursors were Hot in ‘90s

Since IBM Announced Cu Chip in 1997

• Cu CVD was tested by many device makers other than IBM, however, electroplating (IBM’s choice) has been used to manufacture Cu chips.


Metal Oxide Precursors R&D in ‘90s


Many Precursors Developed, However, Not

Used for Semiconductor Manufacturing (1)

• Ba, Sr, Ta, Nb precursors for high-k

dielectric, ferroelectric oxide, etc.

– Metal β-diketonates

(Most are solid.)

– Metal alkoxides

• CupraSelect® for Cu metal CVD

– (hfac)Cu(vtms)


Many Precursors Developed, However, Not

Used for Semiconductor Manufacturing (2)

• Al precursors for Al metal CVD

1. H3Al·NMe3 (solid)

2. H3Al·NMe2Et (liquid)

3. H3Al·(NMP) (liquid)

Thermal Stability

is less than

manufacturable.


Success Stories Seldom Happen (1)

1st high-k Precursor for DRAM

• Trimethylaluminum (TMA) for Al2O3 ALD

film for DRAM high-k dielectric layer

+ O3 Al2O3 film


Success Stories Seldom Happen (2)

2nd & 3rd high-k Precursors for DRAM

• Tetrakis(ethylmethylamido)hafnium (TEMAH) for

HfO2 and tetrakis(ethylmethylamido)zirconium

(TEMAZ) for ZrO2 ALD film for DRAM high-k

dielectric layer

+ O3 ZrO2 film


Semiconductor industry needs

new ALD/CVD precursors

continuously. M. McSwiney (Intel) et al. ALD 2013 Workshop


Precursors are easy to order!

But, it is difficult to meet all the requirements! M. McSwiney (Intel) et al. ALD 2013 Workshop


MANY Precursor Candidates with Various

Metals and Ligands

Limited, still vast possible combinations of metals & ligands!

One good precursor out of HOW MANY candidates?


Drug vs. Precursor Development

1 Successful Precursor

Unit Process Development

Process Integration

Precursor Discovery &

Development-Timeline

A few compounds a dozen or so compounds

Hundreds of compounds

Precursor Discovery


Precursor Makers Have Limited Control

One drug company drives the whole process

(except the initial discovery stage).

1 Successful Precursor

Process Integration Unit Process Development

Precursor Discovery

Under Precursor Maker’s Control

Under Equipment Maker’s Control

Under Device Maker’s Control

What is needed is not the precursor, but film or process result.


Original Drug Is NOT the Only Drug Business


Original vs. Generic Drug Business Model

Original Drug Generic Drug

High risk, high return Low risk, low return

R&D intensive Manufacturing competency

Little competition

by IP protection Competition by price

Drug price ⨠ manufacturing cost Drug price > manufacturing cost


Original vs. Generic Precursors

Who will develop original precursors,

if they can be copied easily by generic makers?


Challenges To Precursor Makers

• No direct access to actual process (which are under equipment and device makers’ control) Unable to determine which precursor is the best.

• Less chance of academic collaboration Only a few academic groups are working on precursor R&D worldwide now.

• Very low Success Rate Few successful precursors out of vast number of candidates.

• Increasing cost for chemical safety There needs to be a way to share the burden.

• Little room for IP protection

– It is obvious now to form a metal-containing film using a volatile metal-containing molecule.

– Product (new precursor molecule) patents are preferable.

Method (process) patents are less useful.


Conundrum : Business Model

• A LOT MORE semiconductor devices will be needed for

self-driving cars, IoT devices, etc., which collect, process,

transmit, and store data.

• A LOT MORE precursors will be used, therefore.

• Will the precursor market diverge?

– Generic precursors market

– High-value original precursors market (for ≤1X nm devices)

• Can original precursor developers get ROI?

• Who will survive?

• Can consolidation be a way out?


Original vs. Generic Precursor Business Model

Original Precursor Generic Precursor

High risk (O)

high return (?) Low risk, low return

R&D intensive Manufacturing competency

Little competition

by IP protection (?) Competition by price and quality

price ⨠ manufacturing cost (?) price > manufacturing cost

Confidential


Summary

• Hard problems can only solved through collaboration of semiconductor precursor, equipment, and device makers.

• There needs to be a way to share burden among participants. (Precursor makers may share safety-related cost. It can make the industry more cost-effective.)

• Precursor makers need business model for ROI.

challenges of ald/cvd precursor development

Technology