Hello All,
I am following the following steps for AZP4903 recipe.
I have bubbles problems
[1]. Dehyrate Sio2 wafer at 150C.
[2] Spin HMDS for 4000 r.p.m for 40 sec.
[3] spin AZP4903 to shoot for the thickness of 15
microns. Spin is usually done for longer periods of
time to evaporate all the solvent in the photoresist.
[4} Softbake the wafer from room temperature to 110C
on contact hot plate. This takes almost 10 mins.
when i expose the photoresist to the light(25mW/cm2).
I have seen bubbles in the PR which were not observed
during the softbaking step.
Can anyone suggest me on this.
Thanks,
Kris