Hi all,

I am trying to pattern a film of   polyvinyl
alcohol(PVA) on Si wafer.
Process steps are:
- Preparation of %4 aqeous PVA solution ( I also have
problems with this, can't obtain   homogenous
solution)
- Spin-coat  of PVA solution @2000  RPM
- Soft bake for 30min @90 C
- AZ1823 PR spin-caoting
- Soft bake for 1 min @90 C
- Exposure of PR and development
- Etching of PVA in DI water for 15 sec
- Drying of substrate and hard-bake for 30 min @140 C
( heat treatment makes   PVA  insoluble in water again
)
- Removal of PR in Acetone. This step  demages  the
substrate, surface becomes white and bloats . I tried
different  hard-bake  times  but nothing changed.

Thank you for your help in advance,



Mustafa Celik

Uludag University
Electrical and Electronics Eng. Dep.
Bursa/Turkey

Mustafa Celik

Uludag University
Electrical and Electronics Eng. Dep.
Bursa/Turkey