My 2 cents:
d.1) while sputter targets don't get evaporation hot (unless you're
doing something horribly wrong) they'll still be very hot and typically
have a much great heated area than evaporation sources so the radiative
thermal load can still be very high
I think the most important thing here is that substrate heating is
highly dependent on the equipment setup and operating parameters. If
you can get away with it you can reduce substrate heating in an evap
setup by increasing the throw distance (though this is of limited
effectiveness as the deposition rate drops with throw as well so the
process takes longer) or cooling the substrate. Using either evap or
sputter you can cool the substrate or pulse the deposition though both
will affect the morphology of the deposited film. No 'easy' answer but
this is an 'engineering' problem that doesn't require invention so a
little elbow grease should get you there.
-----Original Message-----
From: [email protected]
[mailto:[email protected]] On Behalf Of David Nemeth
Sent: Monday, March 05, 2007 8:54 AM
To: 'General MEMS discussion'
Subject: RE: [mems-talk] Thermal issues in metal deposition
I'd add:
d) Radiative heating by exposure to the molten evaporate - high in e
beam
and thermal evaporation, but of course non-existant for sputtering.