You can use a teflon film which can be spun on.  If you are interested,
please let me know.

EH
--------------------------------------------
E.H.Yang, Ph.D
Fujita lab.,IIS, Tokyo Univ.
Tel:+81-3-3402-6231(ext. 2354)
Fax:+81-3-3402-5078
email:ehyang@fujita3.iis.u-tokyo.ac.jp
http://www.fujita3.iis.u-tokyo.ac.jp/~ehyang/yang.html



shpaek wrote:
>
>            Dear MEMS ;
>            I'm searching a passivation material for Si KOH-etching.
>            It takes a long time for Si etching and
>            I must protect front side of wafer.
>            Al layer is deposited on the Front side.
>            Does anyone tell me the material and method of protection?
>
>             Si etch thickness ; 450 micron
>             Si etch solution ; KOH + IPA
>
>            I'll wait for your quick response.
>
>
>            Sincerely yours.
>
>