Suppose I fill a vacuum chamber with 99% oxygen, then pull a vacuum on it down to 10 pascal absolute. If I then vaporize aluminum (for vapor deposition), will the aluminum bind with the remaining oxygen and create say a 0.1 pascal vacuum?

I'm not a chemist or a physicist, but it seems logical that the heavier (and high melting point) aluminum oxide molecules would collect on the walls and floor of the container resulting in a high vacuum mainly containing vaporized aluminum.

I am looking to experiment with aluminum vapor deposition and want to avoid buying a diffusion or turbo molecular pump. Seems like this should work, but I have not found any documentation on it. I'm not looking for optics quality here, so maybe high vacuum is not an issue in the first place.

Let me know if you guys think I should post this on the Physics SE instead. Thanks!

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    $\begingroup$ It is not all that easy to vaporize aluminum in the first place. Nor is it necessary, come to think of it. Then again, do you really need a high vacuum, or just an oxygen-free environment? These are different things, and they are achieved by different means. Your title suggests the former, but your method suggests the latter. $\endgroup$ Apr 26 '17 at 7:33
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    $\begingroup$ In principle yes you could do it, but first bake the system to get rid of water /organics on all the surfaces. Then work out how many oxygen molecules there are left and how many Al ions you are likely to generate; the numbers may be so different that it may take years to do. I recall form some distant memory that a 'getter' may do a similar job. $\endgroup$
    – porphyrin
    Apr 26 '17 at 8:14
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    $\begingroup$ This is essentially how a titanium sublimation pump works. They tend to be operated at orders of magnitude lower pressure, though, to help achieve ultra high vacuum. It may take a while (and quite a lot of power) to deal with 10 Pa of oxygen (plus outgassing water, leaks etc). $\endgroup$
    – AndyW
    Apr 26 '17 at 11:17
  • $\begingroup$ @IvanNeretin, I am not sure if nitrogen and other impurities cause issues when preforming aluminum vapor deposition, but all the literature I have read insists on a high vacuum. I'm not sure what the vaporization temperature of aluminum is in a vacuum, but adding heat to aluminum is the easy part ;-) $\endgroup$
    – ericnutsch
    Apr 26 '17 at 16:40
  • $\begingroup$ @porphyrin, I think I can increase the aluminum vapor to a relatively high concentration which should speed up the reaction. +1 on the "getter" vocab word; I will research more on this. $\endgroup$
    – ericnutsch
    Apr 26 '17 at 16:44

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