I've used the lower viscosity AZ40XT to coat and pattern 40um with good results. I used the vendor recommendations except for a 30 sec longer PEB (2nd one). Here are the bake temps/times. Time Temp Coat Soft bake1 120S 100C Soft bake2 120S 110C Soft bake3 180S 125C Expose PEB1 20S 100C PEB2 120S 105C vendor recommended 90S Develop 4 puddles This resist is chemically amplified so I think the 105 temp is fairly critical. Robert -----Original Message----- From: mems-talk-bounces@memsnet.org [mailto:mems-talk-bounces@memsnet.org] On Behalf Of Haixin Zhu Sent: Tuesday, November 18, 2008 5:26 PM To: General MEMS discussion Subject: [mems-talk] AZ50XT single coat Dear all, I am trying to have 60um thick AZ 50XT on top of quartz substrate, and having some issues with the pattern undercut and film stress, is there anyone who can provide a working recipe since the protocol from the vendor seems not working well. Appreciate the help