Hello Habib,
I've thought about this sort of problem before, and the best idea I could
come up with was to float the wafer in a sonic bath and try to adjust the
frequency/amplitude to get the ripples you want. As far as I know,
nobody's tried this, so it would take a lot of time to figure out your
specific dimensions, if it will work at all.

Just a thought,

Jesse Fowler
  UCLA/MAE Dept., 420 Westwood Plaza, Room 37-129, ENGR IV
  Los Angeles, CA 90095-1597 | (310)825-3977
"Observations of nature, no matter how seemingly arcane, are like
peeling off one more layer from the great onion of knowledge"
    -- Don Petit, ISS science officer

On Wed, 4 Jun 2003, A H M Habib Ahsan wrote:

>
> Dear all:
>
> A flat surface of polyimide layer is found after spun some liquid polyimide
> over a substrate.
> Can anyone suggest me atleast a way that can help me make a change in that
> surface, so that it would no longer be flat, rather something like a lot of
> ripplings with a desired dimension. Each ripple should have dome-shaped pick,
> and the joint of two ripples should be down very near to the bottom surface
> of 2mu thin polyimide layer.
> I would be help.
>
> Thanks
> Habib
> Alberta, Canada
>
>
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