🚀 go-pugleaf

I need to make a 50 microns x 1000 microns section of glass surface
ROUGH. I have  a mask with the required dimensions. Most etchants are
"smooth", and I suspect the common HF based etchants are, too. Are there
any wet chemical etchants that can be used? 
					I also have access to RIE
and RIBE systems, but cannot think of any obvious ways to use them to
make a rough surface - so far, we have always wanted a smooth etch!
We have a full-fledged cleanroom with the usual equipment, so we should
be able to try out most  suggestions, including uncertain leads.

We are trying to make a low reflectivity strip on a mirror. This 
will be used in an external cavity configuration. Initially we thought
of making crossed diffraction gratings, but there will still be a zero
order reflection.. and grating fabrication is a little involved. Hence
we are trying to find ways to make the surface diffusive using some 
form of etching, with the dimensions decided by a mask.

Any suggestions will be helpful. Thanks!

							     swami

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swaminathan srinivasan
center for high tech materials
eece,university of new mexico,
albuquerque, nm 87131, usa			swami@chtm.eece.unm.edu
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