Hi Jong-Ho,

a customer, who uses our wafer holders for KOH etching, applies a
protective PMMA coating on the wafer front side as a safety measure
against over (or through) etching. The material is called X AR-PC
5000/4 and can be obtained from Allresist (www.allresist.de) in
Germany. The polymer is spin coated and an adhesion promoter (also
spin coated) is available as well.

Best regards,

Jan Lichtenberg

--------------------------------

Dr. Jan Lichtenberg

AMMT Advanced Micromachining Tools GmbH
A.-Feuerbach-Str. 6
D-67227 Frankenthal
Deutschland/Germany

Tel.: +49-6233-4960014
Fax:  +49-6233-436214

eMail: mailto:[email protected]
WWW:   http://www.ammt.de

-------------------------
Monday, March 1, 2004, 8:57:20 AM, you wrote:

±> Please help me!

±> I want to etch the back side of silicon wafer using KOH
±> solution without damaging some devices on the front side of wafer.

±> I got a little information there was a photoresist for
±> protecting the devices in case of etching the back side of the
±> wafer. However, I couldn't get the exact information  about the
±> photoresist.

±> As you know the photoresist or chemicals, please let me know it ASAP.


±> Divison of physical metrology/ Mass and Force Lab(NRL,
http://force.kriss.re.kr/)
±> Korea Research Institute of Standards and Science(http://www.kriss.re.kr)
±> P.O. Box 102, Yusong-Gu , Daejeon, 305-600, South Korea
±> Phone : 82-42-868-5241, Fax : 82-42-868-5249, PCS : 016-433-1076
±> E-mail : [email protected], Web: http://my.dreamwiz.com/phdjhkim/