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Why in PVD need vacuum pressure?




Why in PVD process required the low atmospheric pressure (i.e., vacuum air chamber)?

Alan
student - Kuala Lumpur, Malaysia
2006



Hi,

In certain PVD process, one does not want the interfering effects of certain gases like oxygen and hydrogen. in some processes in fact after obtaining vacuum, a steady stream of inert gas like, argon, helium is let in. This inert gas will not only flush out the residual gas but also aids in pushing the reactants (if in vapour form) towards each other. Secondly, low pressure may be a thermodynamic requirement of the reaction.

Sonali Kokane
- Mumbai, Maharashtra, India
2006




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