dear nitin ,
              for gold you can KI+Iodine based etchant
              for Cr you can use 22%Amonium ceric nitrate +8%ch3cooH+H2O
for PECVD you can use BHF ,I think this will work


On Fri, 20 Jul 2007 Nitin Shukla wrote :
>Hello Everyone,
>I have a superlattice structure with following layers in the order:
>
>Au
>Cr
>PECVD oxide (135 nm)
>Si/SiGe SL (0.5 um)
>SiGe/SiGeC buffer (1 um)
>Si wafer
>
>I want to remove Au, Cr and PECVD oxide layers. I was wondering if anyone could
suggest me on what etchants to use so that they selectively remove Au, Cr and
PECVD oxide layers but not the other layers.

Jaibir Sharma
Reasearch Scholar(PhD)
Electrical Department,
IIT Madras,
Chennai - 36
INDIA

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