Thanks a lot. I will try and I will tell you what happened. I have to be careful do not remove the gold from my Si On 4/4/07, Xiaoguang Leo Liuwrote: > Hi Petru > > PDMS is pretty hard to remove once "hard" bonded to SiO2. You can try > to use a blade or your tweezers to rip off the majority of the PDMS > and try HCL:HNO3 3:1 to remove the residual. It worked for me once.