Hi Zeng,

  I think you need adhesive layer between Ni and Si, Ti would work well.. few
hundred angstroms would do for that. Other thing you need to consider is how
thick you are depositing your Ni,  Ni has very high internal stresses.

  Let us know if it works for you

  Regards
  -Chandra

Yiyi Zeng  wrote:
  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?