Scannning Electron Microscope

From Twin Cities Maker wiki
Jump to: navigation, search

This is mostly a placeholder page for our latest acquisition, the Cambridge Stereoscan 260 Scanning Electron Microscope.

The SEM is a complex piece of lab equipment, hard to use and easy to damage. Therefore, members must have training and approval to use the SEM.


Activity log:

7/16/14: Recevied the microscope and located it in the classroom. Replaced twistlock power plug with standard 20A plug to power up and test in the classroom. Reconnected cables that were ripped loose in transit. Installed turbomolecular vacuum pump and connected vacuum system. Machine powers up; unable to achieve and/or verify proper vacuum. The vacuum gauge on the plinth does not light up, and the turbomolecular pump never powers up.

7/17/14: Went over all electrical and vacuum connections again, no change in condition. The problem likely lies in the vacuum gauge control circuitry, which is undocumented. Some odd behavior of the control console was also observed, probably indicitive of more connections which were jarred a bit in transit.

7/18/14: Found and bypassed faulty power swtich on turbomolecular pump control head. Vacuum system now operates properly, but does not reach full vacuum after nearly an hour of pumping. There is probably a leak somewhere, or contamination in the system.

7/27/2014: The SEM is now reaching operating vacuum. According to many references that's 10E-4 Torr, and the console will kick in once the vacuum hits that level. This takes ~5 minutes. However, I'm not able to get more than a brief glimpse of anything on the monitor. The brightness meter never rises beyond one LED, unless the EHT is toggled between low and high power -- then you get a half-second flash of something... I've sent off an email to our benefactor to see if he has any suggestions. --Danbackslide (talk) 00:15, 27 July 2014 (CDT)