Arvind, Transene makes fine etchants as do other companies. I have also used 10% HNO3 90% H3PO4. Brent Arvind Balasubramanian wrote: > Hello all, > > Iam new to MEMS talk and its a pleasure to mail the group. I would like to know if anyone had wet etched aluminum. If so, can you please help me in choosing a etchant. I was looking at Transene Aluminum Etchant. Have anyone used this etchant?