MEMS-talk colleagues:
        We are performing a long SF6 etch on some thin silicon carbide samples
on
a Plasma Therm 790 RIE.  After the etching process is done, I discover that
some of the samples have flipped over or have moved to the extreme edge of
the chamber where the plasma is less intense.  I'm thinking of making a
holder that has wells where I can place the samples and having sufficient
weight that keeps it fixed in location.  Which material can this holder be
made of, such that it would not create a loading effect on the SF6 etch and
would not redeposit onto my sample due to the plasma energy?

Much obliged,
George