Lithographic imaging techniques for the formation of nanoscopic features

Historically, microlithographic technology has followed an evolutionary path where incremental improvements in techniques, materials, and tooling have enabled progress at a rapid rate. In this review we have recounted the reasons why such evolutionary advancement is not likely to suffice for future lithographic imaging at sub-100 nm dimensions. We have described the characteristics of alternate resist and imaging technologies now under development which the industry has termed next-generation lithographies for the sub-100 nm era. While the forces that drive the semiconductor industry virtually ensure that large-scale manufacturing of sub-100 nm devices will take place at some point in the future, it is impossible to predict, at present, which of the candidate technologies will find application there. Both technical and economic considerations play key roles in this decision. Research in the exposure and resist technologies described in this review continue at a swift pace, and a review of the field 5 years from now may be radically different from the current work.