Hallo everyone,

I am having a problem during RCA cleaning / wet chemical etching of SOI
wafers.

1st: After implantation (1e19/cm^3 with boron, 8keV) the 70nm active
silicon were appartently attacked by one of the RCA solutions.

2nd: The burried oxide was apparently etched by HF 1% twice as fast as
ordinary thermal oxide.

We have been wondering whether either material destruction during
implantation or stress in the wafer could be the reason. However, we
have observed this for the first time and it seems to be unclear why!!

If anyone can help, I would be very grateful. Thanks in advance,
Jan F. Eschermann.