Hi, all I am trying to get a undercut profile with AZ 5214 photoresist on Si/SiO2 wafer. It is weird that I always get an overcut profile. Does anyone have any idea about this problem? Here is the recipe I tried: Prebake 95 degree for 45 second Image exposure for 2-5 second at 10mW/cm^2 (Karsuss MJB3 mask aligner) Post bake 45-60 second at 115 degree Flood expose 15-100second Thanks, University of Arizona Quoting BobHendu@aol.com: > HMDS is best done in a YES oven under controlled conditions. You might > contact Bill Moffet at Yield Engineering Services for better instruction. > > It might be to no avail as the work we have done on our new silicon etch > process shows a selectivity of oxide to silicon of around 1:100. If the math > is right you will only be able to etch around 70 microns total before you run > out of hard mask material. You might need to thicken up the oxide and etch it > with plasma to insure proper wall angle before Silicon etch process. Bob > Henderson > > _______________________________________________ > MEMS-talk@memsnet.org mailing list: to unsubscribe or change your list > options, visit http://mail.mems-exchange.org/mailman/listinfo/mems-talk > Hosted by the MEMS Exchange, providers of MEMS processing services. > Visit us at http://www.memsnet.org/ >