A short-pulsed laser cleaning system for EUVL tool

Masami Yonekawa; Hisashi Namba; Tatsuya Hayashi; Yutaka Watanabe

doi:10.1117/12.711357

21 March 2007 A short-pulsed laser cleaning system for EUVL tool

Masami Yonekawa, Hisashi Namba, Tatsuya Hayashi, Yutaka Watanabe

Proceedings Volume 6517, Emerging Lithographic Technologies XI; 65172U (2007) https://doi.org/10.1117/12.711357
Event: SPIE Advanced Lithography, 2007, San Jose, California, United States

Abstract

A traditional method of reticle protection, using a pellicle, is thought to be difficult to apply to EUVL tool. There is a possibility that some particles adhere to the surface of a reticle. In order to resolve this reticle issue, we are investigating in-situ short-pulsed laser cleaning system. In order to confirm whether it can be applied to EUVL tool or not, we have to verify experimentally that it is possible to remove particles in vacuum without any damage to a Mo/Si multilayer. In this work, as a short-pulsed laser, a Q-switched YAG Laser (wavelength: 266~1064 nm, pulse duration time: ~7 ns) has been used. As experimental results, at the pressure on the order of 10^-3 Pa, around 100% removal rate to PSL (organic) particles can be achieved without particular damage using a DUV laser. And also, it is found that a laser cleaning method in vacuum is easier to remove particles on a surface than that in atmosphere and for SiO₂ and Ni (inorganic) particles, this method is particularly effective. This reason can be explained that the drag force exerted to a particle by the surrounding gas molecules is neglected at the pressure on the order of 10^-3 Pa because a gas is in free molecule regime.

Citation Download Citation

Masami Yonekawa, Hisashi Namba, Tatsuya Hayashi, and Yutaka Watanabe "A short-pulsed laser cleaning system for EUVL tool", Proc. SPIE 6517, Emerging Lithographic Technologies XI, 65172U (21 March 2007); https://doi.org/10.1117/12.711357

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available