durusmail: mems-talk: Wavy Surface of 500 micron Thick SU8 layer after Postbaked
Wavy Surface of 500 micron Thick SU8 layer after Postbaked
2006-01-25
2006-01-25
Wavy Surface of 500 micron Thick SU8 layer after Postbaked
Agung Shamsuddin
2006-01-24
Dear friends,

I have applied SU-8 layer with thickness around 500 micron on glass.
I have tried some kinds of softbake procedure:
1.   - 3 hours (from room temp. to around 100 celcius) on hotplate
      - turn of the hotplate to cooling down.

2    - 1 hour (from room temp. to around 65 celcius) on hotplate
      - 1 hour (from 65 degree to around 100 degree ) on hotplate
      - keep on around 100 degree for 2 hours
      - turn of the hotplate to cooling down.

3.   - 1 hour (from room temp. to around 65 celcius) on hotplate
      - 1 hour (from 65 degree to around 100 degree ) on hotplate
      - move to oven which has already set on 95 degree and keep there for 2
hours
      - turn of the oven to cooling down.

I thougth more longer softbake process will remove more solvent.
All the softbake procedure give me flat, smooth and dry (no stick on mask
when exposure) SU-8 layer

and then i exposed  by using recomended exposure dose from manufacturer
datasheet.

and then it continued with postbake.
I have tried:

1.   - 1 hour (from room temp. to around 65 celcius) on hotplate
      - 1 hour (from 65 degree to around 100 degree ) on hotplate
      - turn of the hotplate to cooling down.

2.   - 1 hour (from room temp. to around 65 celcius) on oven
      - 1 hour (from 65 degree to around 100 degree ) on oven
      - turn of the oven to cooling down.

3.  - set the oven on 65 degree, put the specimen inside and keep for 10
minutes
     - 1 hour (from 65 degree to around 100 degree ) on oven
     - turn of the oven to cooling down.

but all the procedure always give me wavy surface of SU8 layer in result.

Please, any opinion and suggestion welcomed.

Best regards,
--
Agung Shamsuddin S.
University of Indonesia
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