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Is it possible to build low cost Ultra High Vacuum Chambers and Atomic Force Microscopes? I found a publication about a low cost AFM and I also found instructions for a Ultra High Vacuum chamber. However the latter is not complete. Are there any more resources on low cost AFMs and UHV Chambers? When I mean low cost I think of a cost of up to 2000€ for each.

eeqesri
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  • You can build almost anything at low cost with sufficient production quantity. Given that there will probably not be a business case including the broad end user, such a price tag is pretty ambitious. Maybe if you can convince a smartphone manufacturer of including an AFM into one of their models... ;-) they are quite ingenious in selling things to people without them noticing that they don't need anything of it. – oliver Apr 11 '21 at 07:39
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    Worth noting that AFM can also be done in air, UHV is not strictly necessary. I guess OP already knows this, but important nonetheless – KF Gauss Apr 11 '21 at 09:35
  • @KFGauss Oh really? I didn't know that! Thanks a lot, that makes things a lot easier. – eeqesri Apr 11 '21 at 09:38

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I think you might be overemphasizing the UHV aspect. Atomic force microscopy can be done in air. Actually in my experience air/ambient AFMs are more common than UHV AFMs. The only reason to use UHV is for dealing with surfaces that degrade in air andor high-sensitivity measurements. It should be relatively cheap and simple to set up an AFM once you let go of the UHV requirement.

Maybe the reason you are thinking of UHV is because the related technique of scanning tunneling microscopy (STM) on the other hand is better performed in UHV. This is because STM because is an electronic technique, is highly sensitive to surface adsorbates/contamination, and has difficulty getting atomic resolution in the presence of air currents. Moreover, it's fairly common to cool to cryogenic temperatures in STM as well to remove thermal broadening.

For comparison, air currents are less of an issue for AFM since the technique is usually done in an AC type mode and has much less lateral spatial resolution compared to STM.

KF Gauss
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It would also depend on the size of the chamber. I have constructed a ‘low cost’ UHV chamber for under 2000€ but this was a very small volume ~ 1 litre. We used a small ion pump and getter from Agilent technologies, and the chamber parts we sourced from LewVac. However, the cost in the chamber isn't the only thing to consider. You will require a ‘roughing pump’ and a turbo molecular pump to reach UHV, both used as pre pump stages before activating the ion pump along with controllers for these. All this would most likely cost more than your chamber setup.

The reason why you are probably struggling to find a resource on low cost UHV setups is because it strongly depends on what you want to do with it, do you require electrical feed throughs, alkali metal dispensers, view ports, AR coated windows etc? And the chambers are always quite specific, I've never come across the same chamber setup in a different lab, although this is from my experience in atomic physics labs, I can't say much for setups in AFM labs.

Some companies we use for vacuum parts are LewVac, Accuglass, Agilent technologies.

I can't say much about AFM setups.

jamie1989
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  • How much did the whole project for the UHV Chamber including pumps and everything cost? Yes I will require electrical feed throughs since I have to measure voltages and I have to be able to view what is happening inside. – eeqesri Apr 11 '21 at 08:08
  • I couldn't give you a precise number without going through all the quotes, which I'm not prepared to do. As a rough estimate I’d say around several thousand. Of course, this also depends on the spec and supplier, you could definitely shop around and even buy second hand pumps. The best thing to do is just design your ideal setup, cost it and downgrade or get rid of what you can if that's too expensive. – jamie1989 Apr 11 '21 at 11:36
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    That being said, I've had AFM measurements taken in air of the surface of our atom chip conductors. Not sure if you really require UHV for your setup though. – jamie1989 Apr 11 '21 at 11:40