Study of acid transport using IR spectroscopy and SEM

Michael D. Stewart; Mark H. Somervell; Hoang Vi Tran; Sergei V. Postnikov; C. Grant Willson

doi:10.1117/12.388353

23 June 2000 Study of acid transport using IR spectroscopy and SEM

Michael D. Stewart, Mark H. Somervell, Hoang Vi Tran, Sergei V. Postnikov, C. Grant Willson

Proceedings Volume 3999, Advances in Resist Technology and Processing XVII; (2000) https://doi.org/10.1117/12.388353
Event: Microlithography 2000, 2000, Santa Clara, CA, United States

Abstract

The migration of acid catalyst molecules from exposed regions into unexposed regions in chemically amplified photoresists and the resulting image blur, has long been recognized as an important topic requiring close study. A fuller understanding of acid transport mechanisms occurring during the post exposure bake is important to help guide the development and formulation of photoresists capable of reliably resolving the increasingly small features required by the semiconductor industry. This paper reports the direct measurement of diffusion coefficients for perfluorobutane sulfonic (nonaflate) acid in poly(4-hydroxystyrene) at several elevated temperatures. These results show that the Fickian diffusion coefficient for nonaflate acid in poly(4-hydroxystyrene) is too small, at typical post exposure bake temperatures, to account for observed isofocal bias. Also reported is a new technique for investigating acid transport properties of photoresist films. This method uses selective silylation to decorate cleaved resist film stacks, so that the extent of acid catalyst migration can be measured directly by scanning electron microscope (SEM). Acid transport distances from the SEM method are compared to those obtained from infrared (IR) spectroscopic techniques.

Citation Download Citation

Michael D. Stewart, Mark H. Somervell, Hoang Vi Tran, Sergei V. Postnikov, and C. Grant Willson "Study of acid transport using IR spectroscopy and SEM", Proc. SPIE 3999, Advances in Resist Technology and Processing XVII, (23 June 2000); https://doi.org/10.1117/12.388353

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