Message-Id:   


Hi

Can you give us a bit more information?  What size of membrane is required
(thickness, diameter)?  Do you mean that you are using silicon as the
support material?  There were some papers a while back in the Journal of
Micromechanics and Microengineering about silicon nitride membranes.  As I
recall, these were produced by PECVD of nitride on both sides of a silicon
wafer, followed by patterning of the nitride on one side, which was then
used as a mask for KOH etching of the silicon.  The resultant membranes were
used in experiments on direct-write e-beam patterning, using very high
acceleration voltages (~400KeV).  The membranes were sufficiently thin to
avoid any back-scattering of the electrons.  This work was done by Prof.
Broers and co-workers at Cambridge University Engineering Department.

Hope this helps.

Martin Walker
***********************************************
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/
***********************************************