Numeric analyses of the roles of gas phase and liquid phase UV photochemistry in conventional and immersion 193 nm lithography

William Hinsberg; Frances A. Houle

doi:10.1117/12.656979

29 March 2006 Numeric analyses of the roles of gas phase and liquid phase UV photochemistry in conventional and immersion 193 nm lithography

William Hinsberg, Frances A. Houle

Author Affiliations +

Proceedings Volume 6153, Advances in Resist Technology and Processing XXIII; 615303 (2006) https://doi.org/10.1117/12.656979
Event: SPIE 31st International Symposium on Advanced Lithography, 2006, San Jose, California, United States

Abstract

We examine the consequences of 193 nm photochemistry of air and water on resist compositions during exposure. The analysis uses a detailed quantitative kinetic model based on available literature mechanistic data and constructed with in-house simulation tools. In conventional 193 nm lithography, both oxidation of the resist polymer due to the UV photolysis of molecular oxygen, and film interaction with strong acids, formed by photo-oxidation of nitrogen and sulfur species in ambient air, have been proposed to lead to degraded resist imaging. We assess the extent to which such reactions can occur under typical lithographic process conditions, and find that while oxidation is minimal, acid deposition into the top of the resist film is significant and can spread over distances of millimeters. Immersion lithography using 193 nm radiation utilizes a layer of highly purified, degassed water as an index-matching fluid. When water is exposed to 193 nm light, short-lived chemical intermediates are produced by two pathways, neutral and ionic. A quantitative evaluation of this photochemistry during lithographic immersion exposure shows that neither type of intermediate nor photolyzed, leached photoacid generator molecules lead to significant water composition changes, so resist impacts are not likely to be marked. Organic immersion fluids may undergo significant photolysis, however there are insufficient experimental data to assess any potential impacts at this time.

Citation Download Citation

William Hinsberg and Frances A. Houle "Numeric analyses of the roles of gas phase and liquid phase UV photochemistry in conventional and immersion 193 nm lithography", Proc. SPIE 6153, Advances in Resist Technology and Processing XXIII, 615303 (29 March 2006); https://doi.org/10.1117/12.656979

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