Solutions with lighteuvlsymposium.lbl.gov/pdf/2011/pres/Torsten Feigl.pdf · Introduction...

Optical performance of 5.5 sr LPP multilayer collectors

© Fraunhofer IOF

Solutions with light – meet challenges and offer opportunities

Optical performance of 5.5 sr LPP multilayer collectors

Optical performance of 5.5 sr LPP multilayer collectors

Torsten.Feigl@iof.fraunhofer.de

2011 International Symposium on EUV Lithography

Torsten Feigl, Hagen Pauer, Marco Perske, Sergiy Yulin,

Marcus Trost, Sven Schröder, Angela Duparré, Norbert Kaiser,

Andreas Tünnermann

Fraunhofer IOF

Angewandte Optik und Feinmechanik Jena, Germany

Miami, October 18, 2011

Optical performance of 5.5 sr LPP multilayer collectors

Contents

Introduction

Characterization of LPP collector substrates

Multilayer coating of LPP collectors

Summary and acknowledgement

Optical performance of 5.5 sr LPP multilayer collectors

Contents

Introduction

Characterization of LPP collector substrates

Multilayer coating of LPP collectors

Summary and acknowledgement

Optical performance of 5.5 sr LPP multilayer collectors

Coating and characterization of LPP collector optics

[Nature Photonics 4, 24-26 (2010)]

Optical performance of 5.5 sr LPP multilayer collectors

LPP collector coating challenges

R > 65 %

l = (13.5 ± 0.03) nm

Dd = 0.015 nm = 15 pm

Diameter: > 660 mm

Lens sag: > 150 mm

Tilt: > 45 deg

Weight: > 40 kg

Optical performance of 5.5 sr LPP multilayer collectors

LPP collector coating challenges

R > 65 %

l = (13.5 ± 0.03) nm

Dd = 0.015 nm = 15 pm

Diameter: > 660 mm

Lens sag: > 150 mm

Tilt: > 45 deg

Weight: > 40 kg

± 15 pm

> 660 mm

+ 25 %

Optical performance of 5.5 sr LPP multilayer collectors

Contents

Introduction

Characterization of LPP collector substrates

Multilayer coating of LPP collectors

Summary and acknowledgement

Optical performance of 5.5 sr LPP multilayer collectors

Surface characterization of EUV collector substrates

No reliable roughness

data available so far:

- complex geometry

- roughness < 0.2 nm

Development of new

surface characterization

based on light scattering

Light scattering:

- fast

- non-contact

- comprehensive

- high sensitivity

Optical performance of 5.5 sr LPP multilayer collectors

Surface characterization of EUV collector substrates

Measurement of ARS

Determination of PSD function

Calculation of roughness (442 nm)

Estimation of HSFR roughness

Optical performance of 5.5 sr LPP multilayer collectors

Measurement of ARS and determination of PSD function

0.01 0.1 1 10 10010-1100101102103104105106107108109

1010101110121013

PS

D (

nm

4)

s ( ° )

i = 0°

i = 45°

HSFR

0.01 0.1 1 10 10010-1100101102103104105106107108109

1010101110121013

PS

D (

nm

4)

s ( ° )

i = 0°

i = 45°

0.01 0.1 1 10 10010-1100101102103104105106107108109

1010101110121013

PS

D (

nm

4)

s ( ° )

i = 0°

i = 45°

-80 -60 -40 -20 0 20 40 6010-8

10-7

10-6

10-5

10-4

10-3

10-2

10-1

100

101

102

103

AR

S (

sr-1

)

s ( ° )

i = 0°

i = 45°

Optical performance of 5.5 sr LPP multilayer collectors

est.

HS

FR

(n

m)

sample 1 sample 2

0.7

0.5

0.3

0.1

0.6

0.4

0.2

0.1 1 10 10010

-1

101

103

105

107

PS

D(n

m4)

f (µm-1

)

position 1

position 2

extrapolation

HSFR=0.14 nm

HSFR=1.07 nm

sample 1sample 2extrapolation

HSFR mapping retrieved from ARS measurements

PSD analysis

Perfect fractal behavior at smooth and rough areas

Prediction of performance at 13.5 nm based on detailed

roughness information (PSD, HSFR)

Optical performance of 5.5 sr LPP multilayer collectors

sample 1 sample 2 sample 2

pre

d.

R (

%)

me

asure

d R

(%

)

65 65

55 55

45 45

35 35

60 60

50 50

40 40

sample 1

Prediction based on roughness data obtained from scattering (before coating)

Reflectance measurements at PTB, Berlin (after coating)

Good correlation between predicted and experimental data Accuracy of average predicted reflectance: DR < 1%

Reflectance drop > 45 %

Optical performance of 5.5 sr LPP multilayer collectors

est. HSFR (nm)

0.7

0.5

0.3

0.1

0.6

0.4

0.2

j=0°

j=20°

j=60°

j=100°

j=140°

j=180°

j=220°

j=40°

j=80°

j=120°

j=160°

j=200°

j=240°

j=280°

j=300°

j=260°

j=320°

j=340°

R=305 mm

Thorough characterization of collector substrate before coating

Check for homogeneity and defects

Fast data acquisition: mapping of entire sample surface (100% characterization)

High sensitivity to roughness (average HSFR = 0.1 nm)

Optical performance of 5.5 sr LPP multilayer collectors

Contents

Introduction

Characterization of LPP collector substrates

Multilayer coating of LPP collectors

Summary and acknowledgement

Optical performance of 5.5 sr LPP multilayer collectors

NESSY – ‚New‘ EUV Sputtering System

Design and realization of an EUV sputtering system

Conception:

magnetron sputtering

of rotating and fast

spinning substrates

up to Ø 665 mm

four deposition targets

deposition of graded

multilayers on curved

substrates

Optical performance of 5.5 sr LPP multilayer collectors

Maximum reflectance along

four lines within clear

aperture of collector mirror:

R ~ 65% @ r < 240 mm

R ~ 62% @ r = 250 … 320 mm

Measurements: PTB Berlin

j = 0°

j = 90°

j = 180°

j = 270°

Reflectivity of LPP collector mirror

Optical performance of 5.5 sr LPP multilayer collectors

Center wavelength along

four lines within clear

aperture of collector mirror:

l = (13.50 ± 0.03) nm

Measurements: PTB Berlin

j = 0°

j = 90°

j = 180°

j = 270°

Reflectivity of LPP collector mirror

Optical performance of 5.5 sr LPP multilayer collectors

Measurement of reflectance

along four lines within clear

aperture of collector mirror:

108 measurement curves

Measurements: PTB Berlin

j = 0°

j = 90°

j = 180°

j = 270°

Reflectivity of LPP collector mirror

Optical performance of 5.5 sr LPP multilayer collectors

52.2 % average area-

weighed reflectance

reached at 13.5 nm

Reflectivity of LPP collector mirrors … climbing the learning curve

Optical performance of 5.5 sr LPP multilayer collectors

Contents

Introduction

Characterization of LPP collector substrates

Multilayer coating of LPP collectors

Summary and acknowledgement

Optical performance of 5.5 sr LPP multilayer collectors

Summary

Characterization of EUV collector optics:

- light scattering technique for HSFR substrate characterization

Multilayer coating of EUV collector optics:

- R > 65 % and d-spacing accuracy of Dd < 15 pm

on world’s largest EUV multilayer mirror (Ø > 660 mm)

Optical performance of 5.5 sr LPP multilayer collectors

Acknowledgements

Cymer for LPP source development: Norbert Böwering, Kevin Cumming, Bruno La Fontaine, David Brandt,

Igor Fomenkov, Alex Ershov, Kay Hoffmann and many others

PTB Berlin team for EUV reflectivity measurements: Frank Scholze, Christian Laubis, Christian Buchholz, Annett Kampe

Jana Puls, Christian Stadelhoff, Martin Biel

EUV project team @ Fraunhofer IOF: Christoph Damm, Andreas Gebhardt, Tobias Herffurth,

Christina Hüttl, Robert Jende, Thomas Müller, Viatcheslav Nesterenko,

Michael Scheler, Thomas Peschel, Stefan Risse, Sebastian Scheiding,

Christoph Schenk, Ronald Schmidt, Mark Schürmann, Uwe Zeitner

Optical performance of 5.5 sr LPP multilayer collectors Thank you!