What happens to the substrate kept in high vacuum and a high temperature of 773K (500oC) and above inside the Vacuum Chamber for a long time?
a) Will the contamination on the substrate removed at high vacuum? b) Any change in the surface of the substrate?
c) Will the surface get oxidized?
d) Destruction of the substrate
e) Any other phenomena. Please give your answer.
There really is too little information to offer a detailed answer, nevertheless:
a) Assuming that the contaminants are not covalently bound with the substrate, are present on the surface of the substrate rather than being enclosed in its structure and are "volatile" in such conditions (e.g. non-polymeric / low molecular weight organic compounds), they will be gradually desorbed from the surface of the substrate. Similarly, the temperature may be sufficient to decompose many organic compounds (and some inorganic species), with the products of such decomposition being potentially more volatile and also being removed in these conditions.
b) This will be dependent on the material of your substrate. If the substrate does not melt or undergo any polymorphic transitions, there should be no such changes, assuming that it is not "volatile" itself under your conditions.
c) No. Assuming the vacuum chamber is operating without faults and was purged with inert gas prior to applying your vacuum source, the traces of oxygen should not be able to oxidise your substrate, at least not to a noticeable extent.
d) Again, this is dependent on the material of the substrate and particularly its melting point and vapour pressure at the temperature you are using. For example, silicon, with a melting point of roughly 1700K and vapor pressure of roughly 0.5Pa at this temperature would be largely unaffected, unless you are using *extremely* high vacuum.
e) Possible solid phase reactions between the substrate and contaminants within that substrate.
Depends on the substrate. Is it a silicon crystal (assuming from your question tags)? High vacuum may not be enough to keep surface clean. High temperature could also promote (rather than prevent) reactions (carbon - silicon).
In addition to the above inquirjes, what was rhe reason of carry on such test/experiment.
If you are resting the vaccuum chamber,therefore refer the manufacturer of the chamber!.
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