Hi Jason,
> I purchased some thin SOI recently to make some fixed-fixed beams and
> cantilevers, and I was assuming that the device layer would be close to
> zero stress (slightly tensile, if anything) and have no stress
> gradients. Having made the structures, it seems that the device layer is
> compressively stressed (the fixed-fixed beams buckle) and has a stress
> gradient (the cantilevers curl upwards). I was wondering if anyone has
> tried to anneal SOI wafers to reduce stress and/or stress gradients, and
> if so, what conditions did you use?
Which kind of SOI are you using ?
For my experience if you use SIMOX SOI you should not have this kind of
problem.
Andrea