the sputtering  is  for  lift off. I'm afraid the Cr could not stand for
enough time, So i do the wet etching before removing the photoresist.  what
about heat the substrate to 80degreeC during sputtering to suppress the
pinhole?

Thank you Mikael

On Tue, Dec 14, 2010 at 12:55 AM, Mikael Evander wrote:

> I'd guess pinholes, a dirty Cr-film or cracks in the photoresist. Do you
> do anything with it after sputtering the chromium? I've had problems in
> the past until I realized that we've incorporated a plasma cleaning step
> of the chromium before depositing the photoresist. It worked great for a
> while but then started to act like your film does. The reason in  my case
> was that someone had started using the plasma cleaner for bonding PDMS and
> that contaminated the film enough to make the photoresist peel and then
> the chromium was attacked and dissolved pretty fast.
>
> Also check that the photoresist isn't cracked or under severe stress from
> baking.
>
> /mikael

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