[mems-talk] Polyimide

[dai truong]

Hi all,
I have used polyimide SU8-2000.5 with a process as following:

·         Spin PR (SU8 2000.5): 10 seconds
500rpm and 30 seconds 3000 rpm (expected PR film thickness 500nm)
·         Soft bake: 60 seconds
·         Expose: 5 seconds 
·         Post Expose bake (PEB): bake at 950C
in 90 seconds
·         Development: 70 seconds and rinse in
IPA 10 seconds
 .       Hard bake (Cure): 2000C
in 15 mins 

but after all, the SU 8-2000.5 film thickness is only  about 300nm, and on the surface some holes occur.  how I can get 500nm-thickness film and cure temperature is enough.
thanks