Hi,

Quartz, like other forms of SiO2, can be etched dry using fluorine
chemistries.  The earliest way of doing this used CF4, but a range of gases
are available now.  Our preference is C4F8.  This has been used to etch a
wide range of structures in quartz, from deep trenches (>10:1 aspect ratio)
to lenses (1:1 selectivity to photoresist).  We (Oxford Plasma Technology)
sell systems to do this, and will also consider offering a service, or could
refer this to people we have sold systems to, who would be able to help.
 Some information is available on http://www.oxfordplasma.com or you could
contact us direct at [email protected].  We have sales and
support both on east and west coast USA, with reps in other areas.  Hope
this is of use.

Martin Walker
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Plasma Technology, Oxford Instruments
North End, Yatton
Bristol, BS49 4AP, England
Tel: +44 (0)1934 833851 Fax: +44 (0)1934 834918
URL http://www.oxfordplasma.com/
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