Chemical and physical aspects of the post-exposure baking process used forpositive-tone chemically amplified resists

Chemically amplified (CA) resists are in widespread use for the fabrication of leading-edge microelectronic devices, and it is anticipated that they w ill see use well into the future. The refinement and optimization of these materials to allow routine imaging at dimensions that will ultimately appro ach the molecular scale will depend on an improved in-depth understanding o f the materials and their processing. We provide here an overview of recent work in our laboratory on the chemical and physical processes that occur d uring post-exposure baking (PEB) of positive-tone CA resists. Our results p rovide a clearer understanding of how this critical step in the lithographi c imaging process will affect extendibility of the CA resist concept to nan oscale feature sizes.