1.Identify imaging capabilities of the SEM
2.There is a collector situated in front of the scintillator in the Everhart-Thornley detector. Let us assume that this collector is under a voltage of i) +200 V, ii) 0 V, and iii) –100 V. Explain the differences, if any, in collection of signals by the detector for three above-listed SEM working conditions.
3: Calculate the maximum theoretical brightness for thermionic (tungsten) emitter operated at 5 kV accelerating voltage and a temperature of 2700K.
4. The filament made of lanthanum hexaboride (LaB6) can produce 5-10 times brighter electron beam than tungsten (W) filament does. Also lifetime of the LaB6 filament is 10 times longer than for the W filament. Explain why we cannot install the LaB6 filament in the JEOL JSM-35C SEM instrument, used in our laboratory sessions
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