Current extreme ultraviolet (EUV) photoresist materials do not yet meet exposure-dose sensitivity, line-width roughness, and resolution requirements. In order to quantify how trade-offs are related to the materials properties of the resist and processing conditions, advanced measurements and fundamental studies are required that consider EUV-resist specific problems. In this paper, we focus on the correlations between the latent image and developed image in EUV exposed line/space features. The latent image of isolated lines produced by EUV lithography are characterized by atomic force microscopy through the change in topology caused by change in film thickness that occurs upon deprotection. The resulting latent-image deprotection gradient, based on line cross-sections, and latent-image line-width roughness provide metrics and insight into ways to optimize the lithographic process. The results from a model polymer and molecular resist show the general applicability of the metric before development.
Proceedings Title: Proceedings of SPIE
Conference Dates: February 22-27, 2008
Conference Location: San Jose, CA
Conference Title: SPIE Advanced Lithography
Pub Type: Conferences
chemically amplified photoresists, molecular glass, photolithography, spin diffusion