| AVS 54th International Symposium | |
| Plasma Science and Technology | Friday Sessions |
| Session PS-FrM |
| Session: | Plasma-Surface Interactions III |
| Presenter: | S. Engelmann, University of Maryland, College Park |
| Authors: | 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 C. Andes, Rohm and Haas Electronic Materials D.G. Nest, University of California, Berkeley D.B. Graves, University of California, Berkeley E.A. Hudson, Lam Research Corp. G.S. Oehrlein, University of Maryland, College Park |
| Correspondent: | Click to Email |
Plasma based transfer of photoresist (PR) patterns into underlying substrates is basic to micro- and nano-fabrication, but suffers from problems like introduction of surface and line edge roughness in the PR/underlying features as a result of plasma processing. In this collaboration, we seek to develop a deeper understanding of the influence of both PR materials and plasma parameters in introducing undesirable changes in PR blanket films and nanostructures. Etch rates, chemical and morphological evolution of fully formulated PR systems as well as carefully selected model polymers have been studied along with a set of sub-micron sized patterned structures using ellipsometry, atomic force microscopy, x-ray photoelectron spectroscopy, and secondary electron microscopy. The current work is designed to complement prior studies on the temporal evolution of plasma-induced PR modifications for a set of different materials processed over a limited plasma parameter range. Using an Inductively Coupled Plasma (ICP) source, a survey of the effects of bias power and voltage, source power, pressure, and feed gas composition (C4F8/% Ar) on 193 nm PR etching behavior and surface modifications has been undertaken. For comparison, PR modifications using discharges based on CF4/H2 mixtures were studied as well. The pure CF4 discharge resulted in a relatively smooth top surface due to high removal rates. But excessive lateral etching caused tapered feature profiles. On the other hand, CF4 discharges admixed with H2 to improve the profile resulted in smooth top surfaces combined with low removal rates similar to C4F8/90% Ar. We also will present results of changes in line edge and width roughness for actual PR nanostructures, and compare these with data obtained using blanket PR films exposed using the same plasma operating conditions.