Narrow polydispersity polymers for microlithography: synthesis and properties

Abstract

The major component of a photoresist formulation is a matrix resin, which therefore has the greatest effect on resist performance. At deep-UV wavelengths the resins of choice are linear phenolic polymers, such as poly(4-hydroxystyrene) (PHOST), which have excellent absorption characteristics within the DUV region. This paper demonstrates the synthesis of a range of narrow polydispersity PHOST polymers (Mn equals 2,000 - 30,000; PD equals 1.1 - 1.4) via a 'living' radical polymerization technique. Further, the effects of polydispersity and molecular weight on the dissolution behavior and thermal properties of these polymers are reported.