Hello Sreemanth.

It can happen that HF diffuses through the resist and etches the wafer
area underneath. Then the resist layer is removed as well.
If that is the case, thickness of resist layer should be increased. The
time for etching is limited.

Best Regards,

Norbert Nodes

-----Original Message-----
From: mems-talk-bounces@memsnet.org
[mailto:mems-talk-bounces@memsnet.org] On Behalf Of Sreemanth M Uppuluri
Sent: Donnerstag, 17. Mai 2007 22:38
To: mems-talk@memsnet.org
Subject: [mems-talk] Quartz Etching

Hello All,

I am interested in etching quartz using photoresist as the mask. From a
reference I found that BHF etches quartz at high speed and does not
affect
Shipley series photoresist. But when I did perform the etch I found that
the
photoresist has all been removed by the BHF solution. Can you please let
me
know what is going wrong. I am presently not using PDMS adhesive layer
before coating photoresist on quartz. Could this be a reason?