|AVS 54th International Symposium|
|Plasma Science and Technology||Friday Sessions|
|Session:||Plasma-Surface Interactions III|
|Presenter:||D.G. Nest, University of California, Berkeley|
|Authors:||D.G. Nest, University of California, Berkeley
D.B. Graves, University of California, Berkeley
S. Engelmann, University of Maryland, College Park
R.L. Bruce, University of Maryland, College Park
T. Kwon, University of Maryland, College Park
R. Phaneuf, University of Maryland, College Park
G.S. Oehrlein, University of Maryland, College Park
C. Andes, Rohm and Haas Electronic Materials
E.A. Hudson, Lam Research Corp.
|Correspondent:||Click to Email|
This study focuses on the relative roles of rare gas ion bombardment and UV/VUV radiation in photoresist (PR) polymer degradation during plasma etch and pattern transfer. We present results of a collaborative study of PR etching and roughening of current generation methacrylate-based 193 nm PR polymers and 248 nm PR. Independently controlled ion and UV sources in a vacuum beam system are used to simulate plasma-photoresist interactions, and the relative importance of UV/VUV radiation and ion bombardment during plasma etch are elucidated. The effects of ion bombardment tend to be concentrated in the near-surface layer. All PR polymers under ion bombardment appear to form a highly cross-linked near-surface layer. By contrast, the effects of UV/VUV radiation, as characterized by transmission Fourier Transform Infrared (FTIR) Spectroscopy, penetrate deeper into the bulk polymer and are more sensitive to the chemical composition of the PR polymer. Surface roughness and morphology depend on the composition of the PR as well as the ion bombardment and UV/VUV exposure protocol. Differences in polymer chemistry are correlated to surface morphological changes. Results from the vacuum beam experiments are compared to measurements made on PR exposed in plasma reactor experiments.