Comparison of EUV resist outgassing between

organic and inorganic materials

Yukiko Kikuchi, Takeshi Sasami, Takashi Kamizono, Shinya Minegishi, Toru Fujimori, Shinji Mikami, Eishi Shiobara

EUVL Infrastructure Development Center, Inc. (EIDEC) Takeo Watanabe, Tetsuo Harada and Hiroo Kinoshita

Center for EUVL, University of Hyogo

P-OC-06

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Introduction

New resist platforms other than traditional CAR need evaluation of outgas impact and risk. ・New resist platforms（non-CAR, nanoparticles, etc.) are unknown with respect to outgassing in an NXE environment. ・Non Cleanable Contamination needs investigation into the impact of the elements used.

Outgas Spec for NXE expired for CAR Announcement from ASML

(in TWG meeting)Cleanable contamination

(Carbon)Non-cleanablecontamination

2011EUVL Symposium 3nm 0.16%

SPIE 2014 10nm 0.16%

SPIE 2015 no spec no spec

Proposal of ASML

But New resist platform, especially metal- containing type are in need of information for outgas risk

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Test sample =Metal Containing Resist (MCR) mimicked Compound

Sample PAG Solvent

A -

B

C

D -

E

Hafnium carboxyethyl acrylate

Dibutoxy Zirconium bis(ethylacetoacetate)

Metal Compounds

Butanol,

PGMEA,

PGME

Butanol,

PGMEA,

PGME

S+ SO3-C4F9

S+ SO3-C4F9

S+SO3

-C4F9

OO

O

Zr

OO

O OC4H9

OC4H9

O

O -

O

O

O

O-O

O

-O

O

O

O

- O

OO

O

Hf 4+

(13 mol%)

(13 mol%)

(4.4 mol%)

11ｗｔ%

5ｗｔ%

12ｗｔ%

TPS-nonaflate

Naphtyl-nonaflate

TPS-nonaflate

Finely coated

Finely coated

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Counter sample from CAR

Sample PAG Quencher Solvent

F -

G

H

Polymer

PGMEA ,

PGME

S+ SO3-C4F9

S+SO3

-C4F9

0.1mol of PAG

N

O O

OH

7030

(～5.6mol%)

20ｗｔ%

(～4.7mol%)20ｗｔ%

TPS-nonaflate

Naphtyl-nonaflate

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Test tool (EUV/EB outgas tester : Witness Sample + RGA)

Exposed Wafer (200mmφ)

Exposed area &size on a Witness sample (1 inch φ)

Exposed Wafer (300mmφ)

Witness Sample Witness Sample

EUV

Exposed area &size on a Witness sample (1 inch φ)

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Contamination Growth (Carbon thickness) on the Witness Sample

HERC (EUV)

EUVOM -9000 (EB)

Not_ tested

A B C D E F G H

Not_ tested

A B C D E F G H

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Carbon Contamination profile on the Witness Samples by Metal Containing Sample exposed by EUVOM-9000 (EB)

No PAG TPS nonaflate Naphtyl nonaflate

Zr- Com pound

D E

Carbon Thickness (nm)

A B C

Hf- Com pound

Measured by Spectrometric Ellipsometer (Woollum M2000X)

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Hf + TPS-nonaflate (sample B)

CAR w/TPS-nonaflate (sample G)

RGA Spectrum of Metal containing sample during EUV exposure (I)

51

44

78 186 18

28

No Hf Peak O

O-

O

O

51

78

186 148

amu78 < amu186

amu78 >> amu186

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RGA Spectrum of Metal containing sample during EUV exposure (II) Hf + Naphtyl-nonaflate (sample C)

CAR w/Naphtyl-nonaflate (sample E)

No Hf Peak O

O-

O

O

18 28

44

78 128 236

148

amu78 << amu128

78 128 236

amu78 ~ amu128

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XPS measurement of Witness Sample exposed by EUV

Hf + TPS-nonaflate (sample B)

Zr + TPS-nonaflate (sample E)

Hf was not observed

Zr was not observed

Carbon 1s Hf4f

Carbon 1s Zr3d

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TOF-SIMS measurements of Metal containing sample (I)

Hf + TPS-nonaflate

HfOx

Negative Ion Spectrum

Sample Coated Wafer

Witness Sample (Exposed Area)

No Hf peak

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Zr + TPS-nonaflate

Sample Coated Wafer

ZrOx

Negative Ion Spectrum

No Zr peak

TOF-SIMS measurements of Metal containing sample (II)

Witness Sample (Exposed Area)

13

Summary The outgassing of model samples for Metal-containing resists: Hf-complex and Zr-chelate w and w/o PAG, were checked by Witness Sample method exposed by EUV and EB.

The Results were;

1. Carbon contamination was observed on Witness sample. It was small w/o PAG, but it was rather large than conventional CAR when the PAG was loaded. 2. The PAG-oriented RGA peaks were clearly found in model samples, where peaks with larger molecules were grater compared to those in CAR. It can be though that the large molecule can rather easily escape from the film composed of small molecules compared to polymer film. 3. The trace of metal was not found in RGA spectrum during exposure, nor on exposed area of Witness Samples by XPS and by TOF-SIMS measurements.

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Acknowledgment

This work was supported by New Energy and Industrial Technology Development Organization (NEDO).

We thank following people for their support for experiments and useful discussions. Mr. Junichi Furukawa Mr. Yosuke Ohta