>Hi All,
 >I am trying to deposit 20 microns of Aluminum in Evaporation or in
 >Sputtering.
 >However, the film is very stress (more stress in sputtering).
 >Do you know a way to reduce the stress for such films?

Hi,
I presume you're worried about extensive tensile stress.
(compressive would almost surely mean contamination)

If you're running high dep. rates without active wafer
cooling, your substrate will become very hot, and CTE
mismatch will create high tensile stress at RT. You
can (partially) anneal this out.

In sputtering, to make stress less tensile, you can
lower temperature
increase dep rate
decrease Ar pressure
increase RF bias

hope this helps
klaus


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