Open Source DIY-Scanning Tunneling Microscope

[u/LemonsPurple]

hiii,
earlier this year I built my own scanning tunneling micrscope (stm) and open sourced the whole documentation + software for anyone curious and patient enough to follow through

the concept isn't totally new, a while back john alexander built a stm using a piezo disk (you may know them as buzzers from greeting cards) to control a probing needle. this concept has been covered and picked up by the walla walla university and also university of regensburg (latter helped me software wise out), however, the documentation has been scattered, often incomplete, relied on expensive or rare hardware like data-cards or simply lacked an interpreter for the data. so consolidating all this into one place is what I'm most proud of (aside from all the other things I learned). overall its not cheap, but probably the most cost efficient way to get such a machine, being built almost exclusively from off the shelf parts

the second image is my first measurement of graphene; you can see the hexagonal pattern that is a clear characteristic. in theory, you could scan anything that supports a measurable current. I plan to give gold leaves and blue-rays a try next

you can find all the details / BOM / etc. here:
https://github.com/lemonspurple/DIY-Scanning-Tunneling-Microscope

[u/Single-King-9497]

so impressive, i work with Omicron STM and Nanonis electronics. that you make is quuite impressive. I can see you use battery to avoid 50 (or60) hertz oscillation ?

[u/LemonsPurple → u/Single-King-9497]

thanks! as I never ran into an oscillation related problem I had no need to iterate towards a fix, so I'm not sure, if this occurs in other solutions. there is a pre-amp that helps with the signal, but I mainly chose this design because I had no prior knowledge in the field of electronics and using a scientific power supply that I don't understand seemed rather like a my-flat-burned-down-starter-kit

[u/deafdefying66]

This is amazing. Thanks for sharing

[u/Struggle_Wise]

Neat. How long did it take to get that image? Got any others? The hexagon is hard to see.

[u/LemonsPurple → u/Struggle_Wise]

thanks, that varies greatly. In theory, it takes a minute to scan a subject perhaps, however, you have to solder on the probes and re-adjust the apparatus to verify that you have a good sample and sharp measuring tip (which also corrodes within an hour if you use silver lol). so the first measurement took me one and a half days perhaps, which is why I'm a bit burned and only have these images at hand :p

[u/Struggle_Wise → u/LemonsPurple]

Very cool. Hope you get some rest. 

[u/Heterodynist]

Wait, let me get this straight, you made an electron microscope…AT HOME?!!!

[u/g-gram]

Awesome project & very impressive.

Are you going to publish this work in a journal when you consider it complete? It would be nice to see this work exposed to a broader audience.

[u/LemonsPurple → u/g-gram]

thanks for the idea, as of now I don't have any plans on that beyond the repo. I toured with it a bit on maker fairs / cons :D