Metal aluminum window screen
Just a few linearity problems ;)
I used an oscilloscope's X and Y amplifiers for these images. It has much better linearity than my own, but not enough differential voltage or offset range.The sum total of the big-ticket items shown in the video is $1485. This does not include hoses, wiring, raw metal, teflon, screws, a cabinet, etc. It also does not include an oscilloscope, which can be a very simple model (under $100 on eBay) as long as it has a z axis (brightness) input. Your diffusion pump or diffusion pump baffle may also require a water chiller.
Here are a list of information sources that helped me with this project:
Teralab - Homebuilt electron gun and other great projects
http://www.teralab.co.uk/Experiments/Electron_Optics/Electron_Optics_Page1.htm
Popular Mechanics video on commercial desktop SEM
http://www.popularmechanics.com/technology/gadgets/4218957
Hamamatsu - Supplier of PMTs
http://sales.hamamatsu.com/assets/applications/ETD/pmt_handbook_complete.pdf
TV to oscilloscope circuit
http://www.electronixandmore.com/project/14.html
CRT oscilloscope clock circuit
http://web.jfet.org/vclk/
Charged particle optics simulation program
http://www.electronoptics.com/
"A Simple Scanning Electron Microscope" P.J. Spreadbury -- Advances in Imaging and Electron Physics Vol 133 Chapter 2.5 (no link).
ISI SEM refurb at home
http://members.tm.net/lapointe2/Scanning_Electron_Microscope.html
Great technical info on cathodes and wehnelt cup spacing. Most of the article concerns LaB6 cathodes, but there is a short paragraph on tungsten cathodes.
https://www.kimballphysics.com/cathode/support_PDF/Cathode_ES423_LaB6_info.pdf
Numerous websites that gave background and operational information about SEMs.
Lots of web searches
Nearly all raw materials for this project were purchased from McMaster-Carr. All power supplies were purchased on eBay, or I already had them, in which case they came from a surplus store or flea market. Nearly all of the electronic components came from Jameco.
