He backside cooling? combined with residual film stress as the substrate
is removed.
If the stress has already been addressed with film stack combination
or intentional low stress film dep - handle wafer might help.
Bill Flounders
Berkeley Microlab

ashwini jambhalikar wrote:
> Dear Friends,
>
> While making 20 micron -40 micron diaphragm in DRIE machine, I have observed
> that the diaphragm gets popped up from the non exposed side.(the side which
> is not seeing plasma).
> Has anybody encountered something similar..what can be the possible cause of
> this..has anybody encountered similar behaviour in wet etching..