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
Sector 72(Indl.Area),S A S Nagar,
Mohali, Punjab- 160071