Hi Sridhar,

I also use the ICP-RIE process with SF6 in combination with AZ
photoresist (in my case 1um AZ 1518) as passivation layer. I also had
problems like you. I solved it with a longer hardbake and an adapted ICP
process flow. I found out, that in may case it obviously was a
temperature problem. So I adapted the process recipe to short etch
periods followed by a cooling period. It is up to you to find out about
the duration. In my case it is about 3 etch cycles (8s etch/4s pass.)
and 1min of cooling, which I aborted by hand when I had the "feeling"
that is was enough (or when I ran out of patience ;-) ).

Regards,
David

Laboratory of Micro-optics
Institute of Microsystems Engineering - IMTEK
University of Freiburg, Germany