A novel photo-thermal setup for determination of absorptance losses and wavefront deformations in DUV optics

K. Mann; A. Bayer; U. Leinhos; T. Miege; B. Schäfer

doi:10.1117/12.775453

7 March 2008 A novel photo-thermal setup for determination of absorptance losses and wavefront deformations in DUV optics

K. Mann, A. Bayer, U. Leinhos, T. Miege, B. Schäfer

Author Affiliations +

Proceedings Volume 6924, Optical Microlithography XXI; 69242P (2008) https://doi.org/10.1117/12.775453
Event: SPIE Advanced Lithography, 2008, San Jose, California, United States

Abstract

Lens heating due to absorbed UV laser radiation can diminish the achievable spatial resolution of the lithographic process in semiconductor wafer steppers. At the Laser- Laboratorium Göttingen a measurement system for quantitative registration of this thermal lens effect was developed. It is based upon a strongly improved Hartmann-Shack wavefront sensor with extreme sensitivity, accomplishing precise online monitoring of wavefront deformations of a collimated test laser beam transmitted through the laser-irradiated site of a sample. Caused by the temperature-dependent refractive index as well as thermal expansion, the formerly plane wavefront of the test laser is distorted to form a rotationally symmetric valley, being equivalent to a convex lens. The observed wavefront distortion is a quantitative measure of the absorption losses in the sample. Thermal theory affords absolute calibration of absorption coefficients.

Citation Download Citation

K. Mann, A. Bayer, U. Leinhos, T. Miege, and B. Schäfer "A novel photo-thermal setup for determination of absorptance losses and wavefront deformations in DUV optics", Proc. SPIE 6924, Optical Microlithography XXI, 69242P (7 March 2008); https://doi.org/10.1117/12.775453

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