Synthesis of novolac resin by acid removal after condensation (ARAC) process

Michelle M. Cook; M. Dalil Rahman; Dinesh N. Khanna

doi:10.1117/12.275859

7 July 1997 Synthesis of novolac resin by acid removal after condensation (ARAC) process

Michelle M. Cook, M. Dalil Rahman, Dinesh N. Khanna

Proceedings Volume 3049, Advances in Resist Technology and Processing XIV; (1997) https://doi.org/10.1117/12.275859
Event: Microlithography '97, 1997, Santa Clara, CA, United States

Abstract

Novolak resins are synthesized by a condensation reaction using a mixture of cresylic acids with a formaldehyde source [paraformaldehyde, trioxane or aqueous (37%) formaldehyde] in the presence of an acid catalyst. After the condensation process, the unreacted cresols, water and solvents are removed using a high temperature (approximately 210 degrees Celsius) vacuum (approximately 20 mm Hg) distillation. The resin is isolated as a molten solid or in solvents such as propylene glycol methyl ether acetate, ethyl lactate, or ethoxy ethyl propionate. During this process, molecular weight changes were noticed. The molecular weight changes were attributed to the presence of residual acid catalyst and the high temperature distillation process. In order to minimize the molecular weight changes, an effort has been made in our laboratories to study the effect of acid removal after the condensation process. Novolak resins with consistent molecular weights could be synthesized using the ARAC process. This paper deals with the novel ARAC process, which has made a major impact on consistency of novolak resins and lithographic characteristics of the resist formulations made with them.

Citation Download Citation

Michelle M. Cook, M. Dalil Rahman, and Dinesh N. Khanna "Synthesis of novolac resin by acid removal after condensation (ARAC) process", Proc. SPIE 3049, Advances in Resist Technology and Processing XIV, (7 July 1997); https://doi.org/10.1117/12.275859

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