Abstract
The design of a sheet-beam electron gun with planar cathode was made with the help of a three-dimensional electrostatic field solver that was capable of forming a sheet-beam of 19 mA at 12 kV. It uses one-dimensional three-fold beam cross-sectional area compression meets the specific requirement of a beam to be formed of height 30 µm and width 600 µm at the beam–waist position with over 100 A/cm2 uniform current density and 0.068 π-mm-mrad emittance, typically, for 0.5 THz devices. A novel beam focusing electrode (BFE) provided with extended-corner rectangular-aperture geometry alleviating the commonly encountered sheet-beam formation problem with a gun that uses a conventional BFE, as well as it reduced beam emittance more than 50%. The practicability of the design was tested by the high-voltage, the thermal and structural analyses. Work has been initiated to test the performance of special high current scandate cathode using anode-aperture mapping.
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Lili Li, Jinshu Wang, Yiman Wang, Anurag Srivastava, Jin-Kyu So, and Gun-Sik Park, accepted for publication, IEEE Trans on Electron Devices (special issue on Vacuum Electronics) (May-2009).
Acknowledgments
The authors would like to thank Professor B. N. Basu for useful comments. This work is supported by Korea Electro -technology Research Institute, Changwon, Korea.
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Srivastava, A., So, JK., Wang, Y. et al. Design of Sheet-Beam Electron Gun with Planar Cathode for Terahertz Devices. J Infrared Milli Terahz Waves 30, 670–678 (2009). https://doi.org/10.1007/s10762-009-9503-9
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DOI: https://doi.org/10.1007/s10762-009-9503-9