AVS 52nd International Symposium
    Plasma Science and Technology Monday Sessions
       Session PS1-MoA

Paper PS1-MoA7
Polymer Management in Advance Dielectric Etch Applications

Monday, October 31, 2005, 4:00 pm, Room 302

Session: Dielectric Etch I
Presenter: G.A. Delgadino, Applied Materials, Inc.
Authors: G.A. Delgadino, Applied Materials, Inc.
D. Buchberger, Applied Materials, Inc.
Y. Zhou, Applied Materials, Inc.
Y. Xiao, Applied Materials, Inc.
Correspondent: Click to Email
Historically, dielectric etch has rely on polymer deposition to achieve desire selectivity to photoresist and barrier film. As features size shrinks, softer shorter wavelengths photoresist are required. In particular, 193nm PR is not only thinner but also more prone to form veils and striations. Heavy polymer deposition is usually used to protect Photoresist and to minimize pinhole formation and striations. Unfortunately fluorocarbon deposited on the wafer and the chamber is released during insitu ashing attacking the barrier layer and sidewall. In this paper we describe the development of a polymer rich recipe that greatly protects photoresist resulting in no top view striation. Minimal barrier loss can be achieved by depositing a thin polymer film over the barrier minimizing barrier loss during ashing. Polymer also deposits in undesired places like the back side of the wafer. Small gaps allow polymer precursors to diffuse in but prevent the ashing plasma to rich the same spots. This deposited polymer might flake during other wafer processing steps reducing yield,@footnote 1@ or might just contaminate other process equipment like the PVD preclean chamber increasing frequency of maintenance. In this work we evaluate intra-chamber and intra-system solutions compatible with low k porous films, to minimize yield loss related to such undesired deposition. @FootnoteText@ @footnote 1@ T. Dalton et. al. AVS 2004.