Hi! We usually have an etch-rate of 1.3 µm/min in borofloat. I'm not sure what you mean with the primer though. We buy borofloat chrome blanks, expose them, hardbake and etch. /Mikael ----- Original Message ----- From: Andrea MazzolariDate: Friday, November 16, 2007 3:28 am Subject: Re: [mems-talk] Best resist for HF etching > Hello Mikael, > which is borofloat etch rate ? Which primer do you use ? > > Best regards, > Andrea.