Xin CHEN, Weiqing XU, Longquan XU, et al. Development of an electron gun operated at intermediate-high energies for electron energy-loss spectrometer[J]. Nuclear techniques, 2017, 40(5): 050102
DOI:
Xin CHEN, Weiqing XU, Longquan XU, et al. Development of an electron gun operated at intermediate-high energies for electron energy-loss spectrometer[J]. Nuclear techniques, 2017, 40(5): 050102 DOI: 10.11889/j.0253-3219.2017.hjs.40.050102.
Development of an electron gun operated at intermediate-high energies for electron energy-loss spectrometer
In an electron energy-loss spectroscopy (EELS) experiment
the electron emitted by the electron gun collides with atoms and molecules
and the momentum and energy of the scattered electron are analyzed by EELS
then the information of electronic structure and collision dynamics of the target can be deduced.
Purpose
2
A well designed intermediate-high energy electron gun with small beam size and divergence angle is needed to satisfy the requirement of EELS.
Methods
2
To obtain the optimal beam condition
the electron optics software SIMION was utilized to simulate the space size and divergence angle of the electron beam at target position
the electron gun has a simple structure
i.e.
consisting of thermionic cathode
grid electrode
anode electrode
focus electrode and deflection plates. The tuning range of electron energy is wide (1-3 keV) and easy to operate.
Results
2
The beam size of 0.95 mm
divergence angel of 0.93°
and beam current of 6.27 μA of the constructed electron gun was obtained at 27 mm from the exit of electron gun at a beam energy of 1.5 keV.
Conclusion
2
An electron gun which satisfies the requirements of EELS has been developed.
关键词
Keywords
references
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