Hello,

I was trying to spin SPR220 on sputtered AU. The
thickness is around 5.5u. I was using AP140 as an
adhesion promoter. The substrate was dehydrated before
spinning AP140.

The PR on the substrate appears to be kind of wavy. I
could see streaks shooting at the edges from the
center. After exposing the PR i could observe that PR
shrinks at some places and results in kind of bubbles.

I was wondering if i am spinning at wrong speeds??

Pls help me

Kris