Dear colleague,

I tried to make Ni pattern with lift-off. I used AC for pretty long
time (30 min, 100W, 20 mT). After I immersed the wafer into aceton,
the PR can not be washed away even with Ultrasonic. The PR is
obviously still there because I can see patterns on the PR layer. Can
I use PR stripper instead of aceton? Is stripper compatible with Ni?
I really appreciate if you can share you experience with me. Thank you
very much for help in advance.

Lee