Dissolution behavior of chemically amplified resist polymers for 248-, 193-, and 157-nm lithography

The aqueous base development step is one of the most critical processes in modern lithographic imaging technology. Sinusoidal modulation of the exposing light intensity must be converted to a step function in the resist film during the development process. Thus, in designing high-performance resists, controlling the dissolution behavior of the resist polymer film in aqueous developer is of the utmost importance. This paper describes and compares the dissolution behavior of different polymers employed in chemically amplified imaging at 248, 193, and 157 nm. The polymers discussed in this paper are polyhydroxystyrene derivatives (248 nm), functionalized poly(cycloolefins) containing carboxylic acid (193 nm), and polymers bearing a hexafluoroisopropanol functionality for base solubility (157 nm).