Hi,

  I'm trying to make some features of about 70 to 80 microns high with
SU-8 2025. I've used the recipe below. However, after the develop and
hard bake the photoresist starts to come off the wafer. So it seems it's
a bonding issue.  Can anyone recommend a recipe for 70 micron high
features with SU-8 2025?

Would a layer of HMDS help the SU-8 bond to the wafer?

Thanks.

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1. PhotoResist
      - Spin 8 sec 500 rpm
      - Spread 30 sec 1250 rpm
      - May Need to wipe perimeter of wafer for excess photoresist

2. Soft Bake
     - 65 deg. C 2 min
     - 95 deg. C 8 min
     - If wrinkles form on cool down try heating up and cooling down again

3. Exposure
     - 20 sec

4. PEB
     - 65 deg. C 1.5 min
     - 95 deg. C 6.5 min

5. Develop
     - Su-8 developer for 6 min

6. Descum

7. Hard Bake
     - Heat from 65 deg C to 160 deg C
     - Let sit at 160 deg C for 10 min
     - Cool down to room temp
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