Gareth,
ECD does work but the yields is very low, especially in thin wafers - they
crack once you make the last hole!

Shay

-----Original Message-----
From: [email protected] [mailto:[email protected]]
On Behalf Of Gareth Jenkins
Sent: Wednesday, December 13, 2006 4:03 PM
To: General MEMS discussion
Subject: Re: [mems-talk] etch through hole on pyrex glass

You could try electrochemical discharge machining (also known as spark
erosion).
I believe two Japanese researchers, Shoji and Esashi, published work on this
a while back, although I can no longer find the reference.