Space-Charge Limited Current from a Finite Emitter in Nano- and Microdiodes

Johannes Bergur Gunnarsson; Kristinn Torfason; Andrei Manolescu; Agust Valfells

doi:10.1109/ted.2020.3037280

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arXiv · 2010.01334

Space-Charge Limited Current from a Finite Emitter in Nano- and Microdiodes

Johannes Bergur Gunnarsson·Kristinn Torfason·Andrei Manolescu·Agust Valfells

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Abstract

We simulate numerically the classical charge dynamics in a microscopic, planar, vacuum diode with a finite emitter area and a finite number of electrons in the gap. We assume electrons are emitted under space-charge limited conditions with a fixed potential applied to the diode. The Coulomb interaction between all electrons is included using the method of molecular dynamics. We compare our results to the conventional two-dimensional Child-Langmuir and explain how it is limited in applicability for sub-micron diameter emitters. Finally, we offer some simple relations for understanding space-charge limited flow from very small emitters.

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Johannes Bergur Gunnarsson, Kristinn Torfason, Andrei Manolescu, Agust Valfells. 2020-10-03. Space-Charge Limited Current from a Finite Emitter in Nano- and Microdiodes. https://doi.org/10.1109/ted.2020.3037280

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