Hello

I am currently using PECVD silicon oxynitride to fabricate optical
waveguides.  However, I am running into a contamination problem when
etching the waveguides.  I am using chromium as an etch mask, and
perfoming the RIE using CF4 and CHF3 in Helium.  The black/grey
contamination appears around the chromium lines, and EDS has shown it to
be mainly carbon-based.

Has anyone else run into a similar problem, or knows how to solve this
problem?  Any help is appreciated!  Please send responses to:
cmarft@ece.ucdavis.edu


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Carl Arft
Dept. of Electrical and Computer Engineering
University of California, Davis
Phone: (530) 754-9249
Email: cmarft@ece.ucdavis.edu
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