Design and fabrication of customized illumination patterns for low-k1 lithography--a diffractive approach: II. Calcium fluoride controlled-angle diffusers

Menelaos K Poutous; Marc D. Himel; William F. Delaney; Jared D. Stack; Alan D. Kathman; Adam S. Fedor; Robert E. Hutchins; Jerry L. Leonard Jr.

doi:10.1117/12.474543

30 July 2002 Design and fabrication of customized illumination patterns for low-k1 lithography--a diffractive approach: II. Calcium fluoride controlled-angle diffusers

Menelaos K Poutous, Marc D. Himel, William F. Delaney, Jared D. Stack, Alan D. Kathman, Adam S. Fedor, Robert E. Hutchins, Jerry L. Leonard Jr.

Author Affiliations +

Proceedings Volume 4691, Optical Microlithography XV; (2002) https://doi.org/10.1117/12.474543
Event: SPIE's 27th Annual International Symposium on Microlithography, 2002, Santa Clara, California, United States

Abstract

As CDs continue to shrink, lithographers are moving more towards using off-axis illumination schemes to increase their CD budget. There have been several papers over the last few years describing various custom illumination profiles designed for application specific optimization. These include various annular and quadrupole illumination schemes including weak quadrupole, CQUEST, and Quasar^TM. Diffractive optics, if incorporated into the design of the illumination system, can be used to create arbitrary illumination profiles without the associated light loss, thus maintaining throughput while optimizing system performance. Diffractive optical elements used to generate efficient illumination profiles for 248 nm and 193 nm excimer laser-source scanners, have been reported and realized in fused silica. The fabrication of such elements in calcium fluoride (CaF₂), for use in 157 nm wavelength lithographic projection tools has been developed and is presented in this paper. Three different categories of elements are shown: large-diagonal-cluster diffusers, medium- and small-rectangular-cluster diffusers. The diffusers were fabricated as binary phase devices, in order to determine calcium fluoride processing capabilities.

Citation Download Citation

Menelaos K Poutous, Marc D. Himel, William F. Delaney, Jared D. Stack, Alan D. Kathman, Adam S. Fedor, Robert E. Hutchins, and Jerry L. Leonard Jr. "Design and fabrication of customized illumination patterns for low-k1 lithography--a diffractive approach: II. Calcium fluoride controlled-angle diffusers", Proc. SPIE 4691, Optical Microlithography XV, (30 July 2002); https://doi.org/10.1117/12.474543

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