Chemically amplified negative resist composition and patterning process

摘要

A polymer comprising 0.5-10 mol% of recurring units having acid generating capability and 50-99.5 mol% of recurring units providing for dissolution in alkaline developer is used to formulate a chemically amplified negative resist composition. When used in a lithography process, the composition ensures an effective sensitivity, makes more uniform the distribution and diffusion of the acid generating component in a resist film, and suppresses deactivation of acid at the substrate interface. The pattern can be formed to a profile which is improved in LER and undercut.