Hi Friends..

        I am depositing a film of Gold(Au) through E-Beam Evapoartion.on
one side of Si wafer. Then i m doing bulk micromachining using KOH on the
other side(with one side protected with gold). But during bulk
micromachining it seems the KOH is attacking Si. This can be observed when
we take out the wafer from KOH, some small domes of gold film can be seen
on the wafer.

        I am suspecting there are some pinholes in the film,throgh which
Si is being attacked.

        My process Coditions are:

        Base Pressure: <5x10-7 torr
        Process Start Pressure= 2x10-7 Torr
        Evaporation Rate: 5-6 ang/sec

        THE PROCESS IS A PR LIFT OFF TYPE PROCESS.

Can anybody suggest how can i solve this problem?

Any suggestion regarding this will be appreciated.

thanks

     Kamal Kishore                     Phone :(0172) 2237401 to 10
     Engineer,VLSI:FAB                 Ext:576,550,570,441
     Semiconductor Complex Limited.    Fax:(0172)-2236378,2236885
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