Resists for fine-line lithography

Resists are radiation-sensitive materials used in the fabrication of integrated circuits (VLSI) for imaging the desired pattern onto the silicon wafer. Most resists in use today consist of polymeric solutions that are spin-coated onto the silicon wafer, exposed in a lithographic tool, developed, and completely removed after the pattern has been transferred to the substrate. This paper presents a historical development of resist materials, present uses of resists, and future requirements, dictated primarily by developments in lithographic tools.