One flavor of DRAM uses a trench of many microns deep to form the storage
capacitor. The trench etch process is a sidewall inhibited DRIE with final
aspect ratio on the order of 30, though absolute depth is not on the scale
of many MEMS process. But it accounts for many millions of parts per year.

Deep trench isolation with similar and smaller aspect ratios are used in
other electronic devices.

-----Original Message-----
From: mems-talk-bounces@memsnet.org [mailto:mems-talk-bounces@memsnet.org]
On Behalf Of Mikael Evander
Sent: Thursday, April 10, 2008 11:24 AM
To: General MEMS discussion
Subject: [mems-talk] DRIE in industry?

Hi.

Does anyone know how common DRIE really is in industry? It seem to
more or less be a fairly common tool in university labs, but is it
actually used in real facilities doing massfabrication as well? I've
always heard that it is slow/expensive and not suited for parallel
processing but the technique should have been refined pretty much
over the years, no?