====== DIY electron microscope ======

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===== Overview =====
Goal of this project is to assess whether is possible to build a scanning electron microscope in DIY conditions. There are various sensors that can be used together with SEM - the easiest one to get running is probably the secondary emission detector. However it would be great if we would be able to use backscatter detectors or even X-ray detector for EDX spectroscopy one day!

It will also be necessary to get some kind of metal sputtering working to be able to view non-metallic samples.

===== Bill of materials =====
(We'll begin with coarse building blocks and discuss details later)
  * Vacuum chamber (we have one, check if it is usable)
  * Base for vacuum chamber with airtight connectors for high and low voltage leads
  * Vacuum pumps system for fine vacuum
  * Various power supplies (accelerating voltage, focusing voltage, heater), exact parameters will have to be calculated
  * electron gun: electron source, electron optics
  * detector (scintillator + photomultiplier)
  * display - for initial tests two channel analog oscilloscope with XY mode and z input should be enough (mrkva can provide one). Later, ADC and digital processing is desirable

===== Proposed roadmap =====
  * Build and test vacuum pump system to see if we can achieve low enough vacuum (something in the range of 10^-6 Pa will be necessary)
  * FIXME

===== Useful sources =====
[[http://www.geo.umass.edu/probe/electron%20optics%20-%20lenses.ppt]]
[[http://www.reu.pdx.edu/SEM%20Short%20Course.pdf]]