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The problem might be with the aluminum hard mask you are using. The amount of
rie used during processing might be responsible for breaking down native al2o3.
This is then a very effective micromask as it doesn't etch in the presence of
fluorine. A more effective mask might be Chrome or photoresist if possible. You
can call me if you would like to discuss further. Bob Henderson 480-968-8818 x
11