directed self-assembly materials development for 7 nm...

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Directed Self-Assembly Materials Development

for 7 nm Node and Beyond

Masafumi Hori 1), Hiroyuki Komatsu 2), Tomohiro Oda 2),

Takehiko Naruoka 2), Tomoki Nagai 2), Motoyuki Shima 2)

1) JSR Micro N.V., 2) JSR Corporation

15/10/26 1st International Symposium on DSA @Leuven

1st International Symposium on DSA 22

Contents

26th Oct. 2015

Introduction: DSA and Challenges for N7 and beyond

JSR materials development

• PS attractive brush for CH application

• BCP for LS application: PS-b-PMMA and High-chi BCP

Summary


ITRS 2013: Technical Trend Targets

26th Oct. 2015

Year of Production 2013 2015 2017 2019 2021 2023

Logic Industry“Node Name” Label

16/14 10 7 5 3.5 2.5

Logic ½ Pitch (nm) 40 32 25 20 16 13

Flash ½ Pitch [2D] (nm) 18 15 13 11 9 8

DRAM ½ Pitch (nm) 28 24 20 17 14 12

FinFET Fin Half-pitch (nm) 30 24 19 15 12 9.5

Pattern miniaturization is continuing for the next decades.How to pattern the layout of 7nm node and beyond?

• ArFi extension• EUV• DSA


JSR: Materials Supplier for ArF, EUV and DSA

26th Oct. 2015

ArF

EUV

DSA

38nmhp LS

Dry/Immersion ArF resist Immersion Top-coat Multi-Layer (SOG/SOC) Process materials (Slimming, Shrink, etc)

13nmhp LS 18nmhp CH High resolution CAR

(13LS & 18CH @NXE3300) Novel metal resist Multi-Layer for EUV

15nm CH9.5nmhp LS Block co-polymer

(PS-b-PMMA & High-chi) Neutral Layer & Brush material Guide pattern material (Resist, SOC)


Challenges of DSA Application

26th Oct. 2015

Placement Error

PS Residue

Gronheid, et al., Proc. of SPIE, 9423_4(2015) Laachi, et al., Proc. of SPIE, 8680_39(2013)

Defect

Gronheid, et al., Proc. of SPIE, 9049_4(2014)

Contribution from materials should be required for solving various challenges of DSA application.


Contents

26th Oct. 2015





Summary

Substrate

PMMA Neutral PS

Sid

ewal

l

PMMA

CD: BCP Pitch = 2 : 1

PS

CD: BCP Pitch = 1 : 1

=> Better placement

accuracy


Grapho-CH: What is a Ideal Guide Surface?

26th Oct. 2015

PS Residue PS ResidueNo Residue

No Residue PS ResiduePS Residue

PS PMMAEffect of Sidewall/Substrate attractively

Surface property control is key technique to solve PS residue issue.

Ideal surfaceGronheid, et al., Proc. of SPIE, 9423_4(2015)


Surface Control using PS Attractive Brush

26th Oct. 2015

Brush

No Brush Brush-1 Brush-2

---

End group type --- A B

CA*

(H2O)

Brush on SOC 40.8 89.4 88.5

Brush on Si 20.5 55.4 89.4

Base polymer End group

(X-linking unit)

PS Attractive Brush

Brush material is effective for controlling guide surface property.Effect of end group on BCP shrink property is evaluated.

*SOC & Si are etched w/ O2 gas

Guide pattern(O2 gas etched)

Surface modification by brush

~90o?

~78o?

~40o

~20o

Ideal

surface?

SOC

Si


Effect of Brush: BCP Shrink Performance

26th Oct. 2015

21.463.5

Guide pattern: imec SOC guide

BCP: 41nm hexagonal pitch26.051.3

End group of brush affects the surface property of guide pattern.Brush-2 shows most PS attractive property.

Patterning Courtesy of imec


Effect of Brush: PS Residue

26th Oct. 2015

No Brush Brush-1 Brush-2

21.4nm 19.9nm

Residue=14.1nm Residue=16.5nm Residue=9.4nm

26.0nm


BCP wet dev.

Backfilling & X-SEM

PS residue could be evaluated by backfilling hole after wet dev. Brush-2 shows less PS residue, but not zero residue.


Discussion for Further PS Residue Improvement

26th Oct. 2015

Brush No Brush Brush-1 Brush-2 Ideal Surface

CA* (SOC) 40.8 89.4 88.5 ~90?

CA* (Si) 20.5 55.4 89.4 75~80?

PS Residue 14.1nm 16.5nm 9.4nm 0nm?

Estimated diagram

Sidewall: PMMASubstrate: PMMA

Sidewall: PSSubstrate: PMMA

Sidewall: PSSubstrate: PS

Sidewall: PSSubstrate: Neutral

PS PMMACA(H2O):

PS=90, PMMA=68*SOC & Si are etched w/ O2 gas

For further PS residue improvement, neutral substrate should be required.Optimization study of Brush-2 annealing condition is carried out.

PS Residue PS Residue PS Residue No Residue


Brush-2 Annealing Study

26th Oct. 2015


Brush-2Annealing

Low Temp. Middle Temp. High Temp.(ref)

CA*(H2O)

Brush on SOC 70.8 83.0 88.4

Brush on Si 74.7 89.2 89.4

X-SEM imagesafter backfilling

Residue=16.6nm Residue=9.4nm Residue=7.0nm

Surface property could be controlled by tuning brush annealing condition. There is not so strong correlation between CA and PS residue.

However, PS residue is reduced by optimizing brush annealing condition.

*SOC & Si are etched w/ O2 gas


Contents

26th Oct. 2015





Summary


BCP for LS Application

26th Oct. 2015

YearLogic Node

Flash Pitch (HP)

L0=30.0nm

20232.5nm16(8)

20177nm

26(13)

201510nm30(15)

20195nm

22(11)

20213.5nm18(9)

PS-b-PMMA

Various research and application study

High-chi BCP

Well phase separationSub-20nm patterning

L0=24.2nm L0=20.9nm

L0=18.3nm L0=14.9nm

1st International Symposium on DSA 151526th Oct. 2015

L0=22.3nmL0=24.2nmL0=30.0nm

FER=2.68 FER=1.87 FER=1.94

100K

300K

FER analysis: Hitachi Terminal PCAfter PMMA etch

L0=24nm and 22nm PS-b-PMMA show FER<2nm after PMMA etching.

Fingerprint Edge Roughness (FER) of PS-b-PMMA



JSR High-chi BCP

26th Oct. 2015

Organic OrganicWet removal unitc=0.09(vs PS)

<20nmP patterning Wet development ability

After Wet Dev.After Coat

Std.Wet Dev.

18.3nmP LS

Organic InorganicSi unit

c=0.12(vs PS) <20nmP patterning Higher etching selectivity

14.1nmP CH 14.9nmP LS 33.1nmP CH

100nm100nm100nm

For Sub-20nmP For >30nmPOrganic-Inorganic Type

Wet Removable Type


Summary

26th Oct. 2015


PS residue is reduced by processing PS attractive brush.

To achieve zero PS residue, PS attractive sidewall & neutral substrate should be required.


L0=21nm lamellae PS-b-PMMA is synthesized.

Various type of high-chi BCP is continuously investigated.


Acknowledgement

26th Oct. 2015

The authors gratefully thank to imec DSA team for various experimental

supports and useful discussion.

• Roel Gronheid

• Paulina Rincon Delgadillo

• Nadia Vandenbroeck

Thank you for your attention !!

directed self-assembly materials development for 7 nm...

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