Hello Paul,

Just to clarify, are you etching the individual die or the whole wafer?  I am
not familiar with KOH etch but I believe you may be able to use a special tape
to protect the front side of the wafer or maybe even the die during the etch
process.  It is normally used during the backgrind process, but it may work for
your etch process.  I would think the tape would be much easier to use than wax.

Mario Robles
650-966-8001 phone
650-966-1881 fax
www.dicingblades.com



-----Original Message-----
From:   BostonMicro@aol.com [SMTP:BostonMicro@aol.com]
Sent:   Friday, December 03, 1999 6:10 AM
To:     MEMS@ISI.EDU
Subject:        Black Wax


I was wondering if anyone new a vendor of Black Wax. I need to KOH etch the
back side a chip, but don't want to destroy my devices on the front.

Thanks in advance,

Paul Bierden

President
BMC
Boston Micromachines Corporation