Figure 1. Titanium Sublimation Pump (TSP)
3.2.
Liquid Nitrogen (LN2) cryoshroud
A cryoshroud provides capture and hold of water (H
2
O) and carbon dioxide
(C0
2
) pumping when cooled with liquid nitrogen (LN
2
).
It provides a surface for sublimated titanium while preventing line of sight
migration of titanium (Ti). Cryoshrouds can be used with and without
coolants. Recommended coolants include: water and LN
2
. When used with
LN
2
, hydrogen pumping speed is increased by a factor of 6.5.
Figure 2. Liquid nitrogen cryoshroud
3.3.
Ambient sputter shield
An ambient sputter shield provides a surface for sublimated titanium while
preventing line of sight migration of Ti. It is low cost and is smaller than the
cryoshield.
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900035_B
900035_B - Introduction
