© imec 2005

Lithography Roadmapwithout immersion lithography

32 nm45 nm65 nm90 nm130 nm180 nm 22 nm

248nm

193nm

157nm

EUVL

1999 20022001

20042003

20072005

20102007

20132009

3-year cycle:2-year cycle:

20162011

Node

45 nm65 nm90 nm130 nm180 nm250 nm 32 nmHalf pitch

© imec 2005

Lithography Roadmapwith immersion lithography

32 nm45 nm65 nm90 nm130 nm180 nm 22 nm

248nm

193nm

157nm

EUVL

1999 20022001

20042003

20072005

20102007

20132009

3-year cycle:2-year cycle:

20162011

Node

45 nm65 nm90 nm130 nm180 nm250 nm 32 nmHalf pitch

1.1-1.2NA

© imec 2005

Lithography Roadmapwith immersion lithography

32 nm45 nm65 nm90 nm130 nm180 nm 22 nm

248nm

193nm

157nm

EUVL

1999 20022001

20042003

20072005

20102007

20132009

3-year cycle:2-year cycle:

20162011

Node

45 nm65 nm90 nm130 nm180 nm250 nm 32 nmHalf pitch

1.1-1.2NA

~1.2NA

© imec 2005

157nm has no window

Max Resolution with High Index Fluids with sinθ=0.93

30

35

40

45

50

55

60

65

1 1.1 1.2 1.3 1.4 1.5 1.6Refractive Index

Res

olut

ion

@ k

1=0.

3 (n

m) 193nm

157nm

PFPE Fluid high-n

• ArF water immersion replaces F2 dry

Fluid x

needed

• ArF fluid high-n immersion replaces F2 -PFPE

Dry

Water

© imec 2005

SPIE 2005 Fluid highlights

SPIE, M arch 1, 2 005

Testing at 32nm with Dupont IF131 and IF132 High-n Immersion Fluids

(Initial Fluid Screening)

IF131 IF132Similar imaging performance from the two fluids, both very good!

32nm Lines (pitch 64nm)

© imec 2005

Lithography Roadmapwith immersion lithography

32 nm45 nm65 nm90 nm130 nm180 nm 22 nm

248nm

193nm

157nm

EUVL

1999 20022001

20042003

20072005

20102007

20132009

3-year cycle:2-year cycle:

20162011

Node

45 nm65 nm90 nm130 nm180 nm250 nm 32 nmHalf pitch

1.1-1.2NA

~1.2NA

1.3-1.5NA

© imec 2005

Lithography Roadmapwith immersion lithography

32 nm45 nm65 nm90 nm130 nm180 nm 22 nm

248nm

193nm

157nm

EUVL

1999 20022001

20042003

20072005

20102007

20132009

3-year cycle:2-year cycle:

20162011

Node

45 nm65 nm90 nm130 nm180 nm250 nm 32 nmHalf pitch

1.1-1.2NA

1.3-1.5NA

© imec 2005

k1 factor

90 65 45 32 22

0.75 0.35 0.25 0.17 0.12 0.09

0.85 0.40 0.29 0.20 0.14 0.10

0.94 0.44 0.32 0.22 0.16 0.111.05 0.49 0.35 0.24 0.17 0.121.2 0.56 0.40 0.28 0.20 0.14

1.35 0.63 0.45 0.31 0.22 0.15

1.5 0.70 0.51 0.35 0.25 0.171.65 0.77 0.56 0.38 0.27 0.19

1.8 0.84 0.61 0.42 0.30 0.21

Half Pitch Technology Node [nm]N

A [@

193

nm

]NA

kresolution λ.1=

© imec 2005

Lithography Roadmapwith immersion lithography

32 nm45 nm65 nm90 nm130 nm180 nm 22 nm

248nm

193nm

157nm

EUVL

1999 20022001

20042003

20072005

20102007

20132009

3-year cycle:2-year cycle:

20162011

Node

45 nm65 nm90 nm130 nm180 nm250 nm 32 nmHalf pitch

1.1-1.2NA

1.3-1.5NA

© imec 2005

Rayleigh equation

NAkresolution λ.1=

Lord Rayleigh

k1 scaling

Double exposure techniques

© imec 2005

Double dipole imaging

Random logic

DY

DX

© imec 2005

Impact of polarization on SRAM active layer print (110 nm pitch)

DY40 0.96/0.76

Unpolarized Polarized

E=25.8CD=51.5

E=24.6CD=56

E=23.4CD=58

E=22.2CD=60

E=21CD=59

23 % EL

DryNA=0.93

© imec 2005

Double patterning (2x litho + 2x etch)

SiNitride HM

Resist

Int.Exposure 1

& development

Transfer tohardmask

Int.Exposure 2

& development

Transfer tohardmask

Exp.

1

Exp.

2

Pitch = 100nmCD=50nmk1=0.19

100nm pitch

50 nm L&S with 0.75NA

© imec 2005

Double patterning complex pattern

1st exposuredevelop and etch

2nd exposuredevelop

+

etch

=

150-nm pitchNA = 0.75193 nm k1 = 0.29

© imec 2005

Double exposure technique

CoO considerations

Requires 2 critical masksReduces throughput (~ factor 2)Adds cost of hard mask and etchCritical overlay requirementImpacts cycle time (additional photo, etch, …)

© imec 2005

Outline

Introduction

193nm immersion lithography

EUV lithography

Global collaboration

Conclusions

Status, ChallengesEUV lithography

© imec 2005

EUV lithographyMain technology challenges

Multilayer coated optics

High powersource

Thin resistHighly sensitive

Low LER

MaskDefect Free

Multilayer coated

Pellicle free mask

CxHy, OopticsSource induced

contamination

Contaminationcontrol

© imec 2005

EUV tool integration progress

servo, vacuum, water,electronics cabinets

reticle stage

wafer stage

reticle handler

wafer handler

source-collectormodule baseframe

servic

e

corr id

or

0.25 NAfull field

© imec 2005

EUV tool integration progress

servo, vacuum, water,electronics cabinets

reticle stage

wafer stage

reticle handler

wafer handler

source-collectormodule baseframe

servic

e

corr id

or

© imec 2005

Multilayer coated optics

High powersource

Thin resistHighly sensitive

Low LER

MaskDefect Free

Multilayer coated

Contaminationcontrol

EUV lithographyMain technology challenges

© imec 2005

Multilayer coated optics

High powersource

Thin resistHighly sensitive

Low LER

MaskDefect Free

Multilayer coated

Contaminationcontrol

EUV lithographyMain technology challenges

EUV mask cross section(TEM courtesy of AMD)

Absorber

Buffer

Low thermal expansion substrate

Absorber

Buffer

Multilayer

Substrate

Absorber

Buffer

MultilayerM

ask

blan

kM

ask

mak

ing

no pellicle during exposure

© imec 2005

Multilayer coated optics

High powersource

Thin resistHighly sensitive

Low LER

MaskDefect Free

Multilayer coated

Contaminationcontrol

EUV lithographyMain technology challenges

SEMATECH MBDC EUV Blank Defect Progress

0.001

0.01

0.1

1

10

100

Sep-03 Dec-03 Mar-04 May-04 Aug-04 Nov-04

Defe

ct D

ensi

ty (d

/cm

^2 @

80

nm)

ML Adders + DecorationML AddersTotal DefectsPMsGoals

Q104 goal: 0.3 @ 90nmQ204 goal: 0.12 @ 80nm

Q404 goal: 0.08 @ 80nm

Significant progress in defect reduction

© imec 2005

Multilayer coated optics

High powersource

Thin resistHighly sensitive

Low LER

MaskDefect Free

Multilayer coated

Contaminationcontrol

EUV lithographyMain technology challenges

0.1

1.0

10.0

100.0

1000.0

Jul-0

1

Jan-

02

Jul-0

2

Jan-

03

Jul-0

3

Jan-

04

Jul-0

4

Jan-

05

Jul-0

5

Jan-

06

Date

EUV

Pow

er a

t Int

erm

edia

te F

ocus

[W] 115 W production requirement

Exponential fit to dataAverage of reported

Data from Sematech EUV Source Workshops

Fast progress on system productivity (source power)

© imec 2005

Multilayer coated optics

High powersource

Thin resistHighly sensitive

Low LER

MaskDefect Free

Multilayer coated

Contaminationcontrol

EUV lithographyMain technology challenges

Optics substrate

Multilayer coated optics

(Images courtesy of VNL / EUVLLC)

© imec 2005

Multilayer coated optics

High powersource

Thin resistHighly sensitive

Low LER

MaskDefect Free

Multilayer coated

Contaminationcontrol

EUV lithographyMain technology challenges

Edge variation over certain line length isLine Edge Roughness

increasing exposure dose

Better edge definition

Resist Sensitivity vs.Line Edge Roughness(trade off)

© imec 2005

Multilayer coated optics

High powersource

Thin resistHighly sensitive

Low LER

MaskDefect Free

Multilayer coated

Contaminationcontrol

EUV lithographyMain technology challenges

Resist Sensitivity vs.Line Edge Roughness(trade off)

SensitivityResolution

Line Edge Roughness

Shot noisestatistics

DiffusionLength

© imec 2005

HO O

O

O

OHO

O

O

t-Boc

t-Boc

t-Boc

t-Boc

t-Boc

t-Boc

New Resist Approaches

10.0mJ/cm2 Bright Field (Courtesy of Prof. Chris Ober, Cornell University)

Cornell University

Positive-tone Molecular Glass Resist

Shorter polymers may provide a possible solution

40 nm (2:1)40 nm (2:1)

60605050454540403535

2:12:1

© imec 2005

hp 32nm options

NA k1 λ

NAkresolution λ.1=

ArF Immersion1.8 NA(k1=0.3)

Single exposure

Lens size and cost

Liquid (nf>1.8)

New lens material (nf>1.8)

ArF Immersion1.35 – 1.5 NA

(k1=0.22)

Doubleexposure

Cost of mask (2x)

Throughput reduction

Cost of additional process steps (hard mask dep/etch)

Overlay requirement

EUVL0.25 NA(k1=0.6)

Single exposure

Defect free mask- Mask blank defect density- No pellicle during exposure

CoO- Source power- Optics lifetime- Resist sensitivity

Critical challenges:

© imec 2005

Outline

Introduction

193nm immersion lithography

EUV lithography

Global collaboration

Conclusions

Global collaboration

© imec 2005

Research challenges require…

World-wide Research Partnershipsbetween

ResearchOrganization

ICManufacturers

EquipmentSuppliers

© imec 2005

imec 193nm Immersion programThe world’s largest 193nm immersion lithography effort

LamRESEARCH

STMicr oelectronicsSTMicr oelectronics

True global partnership

© imec 2005

International EUV Initiative…

IEUVI International

EUVInitiative

IEUVI Chairman:Paolo Gargini :

Europe:• MEDEA+• LETI• IMEC

Japan:• ASET• EUVA• MIRAI

US:EUV LLCSEMATECHVNLSRC

IEUVI Technical Working Groups (TWG)

Mask TWGChair: Phil Seidel SEMATECHOrganizer: Shinij Okazaki EUVA

Optics TWGChair: Ginger Edwards SEMATECH / FreescaleCo-Chair: Yasuaki Fukuda EUVA / CanonOrganzier: Giang Dao SEMATECH / Intel

Source TWGChair: Koichi Toyoda EUVA Co-Chair: Stefan Wurm SEMATECH / InfineonOrganizer: Dieter Goltz MEDEA

Resist TWGChair: Kim Dean SEMATECH Co-Chair: Wolf-Dieter Domke InfineonOrganizer: Serge Tedesco CEA / LETI

…an International Consortium Network

e.g. Mask handling solutions

© imec 2005

Outline

Introduction

193nm immersion lithography

EUV lithography

Global collaboration

ConclusionsConclusions

© imec 2005

Conclusion

ArF immersion has eliminated 157nm lithography

Phenomenal progress has been obtained for ArF immersion lithography in less than 24 months

End 2003: ASML/IMEC demonstrated first data on immersion feasibility prototype scanner (0.75NA AT1150i)End 2004: Two development scanners (0.85NA) have been installed in the field

Key challenges for immersion have been identified; solutions have been proposed/demonstrated for all issues

In order to cope with the extremely short introduction time, world-wide partnerships and collaboration have proven to be very effective

ArF immersion is clearly usable down to at least hp 45nm

hp 32nm is unlikely to happen with immersion lithography and is believed to be the introduction node for EUVL

Significant progress has been made on the most important critical issues for EUVL (mask defects, source power, …)

© imec 2005

Acknowledgement

Many people have contributed to this presentation

IMEC lithography team (K. Ronse, G. Vandenberghe, …)

ASML (M. van den Brink)

ZeissSematech (S. Wurm)

© imec 2005

© imec 2005

Immersion Lithography

However, early 2004:

Feasibility study of IMMERSION LITHOGRAPHY successful

Several advantages (over 157nm) :

Build further on “mature” 193nm resistsMajority of optical material remains fused silica (not CaF2)Same reticle materials continue to be used

No thick Qz pellicles neededNo modified Qz blanks needed

© imec 2005

Resolution outlook

303234363840424446

1.5 1.6 1.7 1.8 1.9 2index [-]

half

pitc

h [u

m] k1=0.3

k1=0.27

38-nm with new fluid andNew lens

32-nm requires

very high index