Photoresists for 193-nm lithography

Photolithography using 193-nm light appears to be a viable route for the extension of optical lithography to the dimensions required for the manufacture of 1Gb DRAM and advanced CMOS microprocessors with 180-140-nm minimum feature sizes. In this paper, we discuss the origin of resist technology for 193-nm lithography and the current status of 193-nm photoresists, focusing on single-layer resist materials. We emphasize the photoresist design approaches under investigation, compare these with deep-UV (DUV) (248-nm) resist design and materials, and consider possible future lithography processes employing 193-nm lithography. Research and development on 193-nm photoresists by the lithography group at the IBM Almaden Research Center is highlighted.