[mems-talk] Thermal issues in metal deposition

[David Nemeth]

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.  

-----Original Message-----
From: mems-talk-bounces at memsnet.org [mailto:mems-talk-bounces at memsnet.org]
On Behalf Of MT Klaus Beschorner
Sent: Monday, March 05, 2007 5:51 AM
To: mems-talk at memsnet.org
Subject: [mems-talk] Thermal issues in metal deposition

To contribute to an already heated :-) discussion:

Substrate heating in metal deposition has three main contributors:
a) heat of condensation of the metal atoms
b) kinetic energy of arriving atoms
c) resistive heating by secondary electrons

In more detail:
a) is entirely material dependant, and is usually between
    1(Cd) and 9(W) eV/atom
b) depends on the deposition process used, usually <1eV/atom for
    evaporation, 2-10eV for sputtering, up to 50eV for iPVD.
c) usually low for evaporation, can be very high in sputtering
    sources without proper magnetic confinement of secondary
    electrons emitted from the target.