Patent ID: 7396482
Filing Date: 2008-07-08
Classification: G03F,H01L

Abstract:
1. An immersion lithography method for lowering the water variation in a resist during the forming of a semiconductor device, the method comprising: forming a resist layer on a substrate, said resist layer having a top coat with an inhomogenity therein and said resist having a thickness; using immersion lithography to expose the entire thickness of the resist layer to patterned irradiation prior to any heating to a temperature that is equal to or greater than a deprotection temperature, said inhomogenity in said top coat generating a local water variation in the resist layer and said patterned irradiation generating a photoacid throughout the entire thickness of the resist layer; heating the exposed resist layer at a first temperature that is lower than the deprotection temperature of the resist layer to remove said local water variation; heating the exposed resist layer at a second temperature subsequent to removing said water variation, wherein the second temperature is between a low temperature of about 100° C. and a high temperature at least equal to the deprotection temperature of said resist layer; and developing said entire thickness of the resist layer, subsequent to said steps of exposing and heating at said first and second temperatures, to provide a patterned resist.