Dear all, I'm working on deep dry etch of p-Si (>10um) and I was trying to evaporate Ni as etch mask. I was trying to use lift-off technique and my photoresist was AZP4110. The problem is when I was washing away the photoresist using Acetone, almost all of the Ni, no matter on the photoresist or on the Si, fell off the wafer. I tried three times and the results were same, but when I previously evaporate Al and Cr, I didn't see this kind of problem. I'm wondering if anyone has the similar experience? Did I do anything wrong? Any suggestion to improve the process? Thanks a lot! Best regards, Yiyi