Practical Considerations
When mounting the TSP in the chamber, a number of important considerations must be made. First, it is desirable that the filament can deposit on a large area. However, one must take care that the titanium is not deposited onto anything it can damage. For example electrical feedthroughs containing ceramic insulators will fail if the titanium forms a conducting film which bridges the ceramic insulator. Samples may become contaminated by titanium if they have line-of-sight to the pump. Also, titanium is a very hard material, so titanium film which builds up on the inside of the chamber may form flakes which fall into mechanical components (typically turbomolecular pumps and valves) and damage them.
Many chambers containing TSPs also have an ion pump. Often the ion pump provides a good location for the TSP, and some manufacturers promote the use of combined TSP/ion-pumps. Furthermore, TSPs have been shown to be effective against the regurgitation effects of ion pumps.
Read more about this topic: Titanium Sublimation Pump
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