Similair stiction problems have been circumvented by using a dry release process
using standard photo resist as supporting layer after sacrificial wet etching.

The process is the following:
1: Sacrificial wet etch of SiO2 (BHF)
2: Rinsing H2O (the sample with the suspended cantilever is never allowed to
drie out)
3: Apply Acetone
4: Apply Photo resist in large amounts until the liquid covering the sample is
"only" consentrated photo resist
5: Spin at 1500 rpm for a short time of 30s
6: soft-bake 1 min
7: Use oxygen plasma ashing in a RIE for the dry release (99:20 sccm O2:N2, 30
W, 80 mTorr for 15 min)

Regards
__________________________________________________

Esko Forsén
Ph.D. Student, Bioprobes project
MIC - Mikroelektronik Centret
Technical University of Denmark

Address: Oersteds Plads, DTU Building 345 east
             DK-2800 Kgs. Lyngby, Denmark

Tel. Direct:    +45 4525 5733
Fax:            +45 4588 7762

E-mail:         ef@mic.dtu.dk
www:    www.mic.dtu.dk
__________________________________________________


-----Original Message-----
From: Saurabh Nishant [mailto:nishu7uf@yahoo.com]
Sent: 24. oktober 2003 13:16
To: mems-talk@memsnet.org
Subject: [mems-talk] polysilicon stiction problem


Dear MEMS colleagues,
  I am a student at indian institute of science and facing the problem of
stiction in polysilicon cantilivers after sacrificial layer etching.I would
appreciate if any one can suggest me some means to overcome this problem.I
suspect both the resifual stress and capillary forces are reponsible.Any help
would be highly appreciated.
thanks.

regards
nishant


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