Patent,
Method to prevent backside growth on substrates in a vapor deposition system
(1990)
Abstract
Backside growth on substrates in a vapor deposition system has been
a problem resulting in cracking of the material deposited on the
substrate, making replication in a vapor deposition system difficult
to achieve, and requiring post deposition machining to separate the
substrate-deposit from the deposition fixture. A solution to the
problem is the following: the substrate is mounted on a plurality
of graphite pillars, with the pillars being bonded to the substrate
as near the periphery thereof as possible. A hollow body open on
one side but closed on the other, and fabricated from GRAFOIL with
graphite cement used as a bonding agent, is mounted on the pillars
with the open end facing the substrate. The open end of the body
is pressed against the substrate and sealed with a bonding agent.
This completely covers the backside of the substrate and thus prevents
any vapor deposition thereon.
