Hey Renil,

The hard mask is sputtered Al with thickness of 1500A and the the depth
etched down to silicon is about 10um.

I applied an etching cycle of 3s and a passivation cycle of 1s. The flow
rate of SF6 = 200sccm and C4F8 = 100sccm.

I've heard lowing the passivation flow rate might help with grass problem,
but not quite sure.

My Best,

Li. Zhang
---------
Graduate Student
Edward P. Fitts Department of Industrial and Systems Engineering
North Carolina State University
Raleigh, NC 27695-7906
USA
TEL: (919) 413-5459
Email: lzhang13@ncsu.edu
Web:  http://www.ise.ncsu.edu
         http://www.nnf.ncsu.edu