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Can you image non-conductive surfaces with this technique?
Nope, the technique for that is an Atomic Force Microscopy[1]. 1: https://en.wikipedia.org/wiki/Atomic_force_microscopy
1: https://en.wikipedia.org/wiki/Scanning_helium_ion_microscope
Home Built Scanning Tunneling Microscope Electronics - https://news.ycombinator.com/item?id=9752215 - June 2015 (9 comments)
Home-Built Scanning Tunneling Microscope - https://news.ycombinator.com/item?id=8884085 - Jan 2015 (1 comment)
CA3140 OpAmps also work well. The comments about 1pF feedback do speak to one of the challenges with feedback stability, where stray capacitance on the proto-board may or may not be present.
Indeed, a 100-Meg feedback resistor is mostly a capacitor. You could think of it as an integrator with DC bias control. This is probably the best article I've seen about transimpedance amplifiers: https://electrooptical.net/static/oldsite/www/frontends/fron...
Can you image non-conductive surfaces with this technique?
Best you can do is gold plate the object you would like to scan. Sputter coating is the preferred method. https://en.wikipedia.org/wiki/Scanning_electron_microscope#S...
Can you image non-conductive surfaces with this technique?
STM is frequently used to characterize adsorbed molecular monolayers on a graphite substrate.
You're obviously depending on electron conduction to image the sample, but you can image all sorts of things which wouldn't be considered conductive as a bulk material.
Ben Krasnow built his electron scanning microscope back in 2011. I never expected to see that one upped. https://benkrasnow.blogspot.com/2011/03/diy-scanning-electro...
Homebrew SEM is probably much more difficult and rare.
My first thought is, the implant business has now got a problem. Soon enough, anyone and their pal will be able, finally, to validate their silicon at adequate scale.
I think I'm going to build this with my kids. What better way to show them atoms than to actually make them build a microscope that shows you the things directly?
But its not showing things directly, is it? Its interpreting a frequency and converting that to an image. Is it really that different to a music visualiser?
I think I'm going to build this with my kids. What better way to show them atoms than to actually make them build a microscope that shows you the things directly?
I'm sure its a cool project. But its not showing things directly, is it? Its interpreting a frequency and converting that to an image. Is it really that different to a music visualiser?