Thermionic and Photon-Enhanced Emission from CVD Diamond: Influence of Nanostructure, Doping, and Substrate

Abstract:

Thermionic electron emitters based on doped diamond films have shown significant emission at less than 500°C. Results have established that it is necessary to control the electron affinity, doping levels and concentration, and band bending, and these properties have been achieved with engineered multilayered structures with controlled morphology, doping and substrate. Recently, visible light photo-electron emission has been demonstrated using the same diamond film emitters. This report presents a spectroscopic and surface electron microscopy study of photo-and thermionic emission from nitrogen doped diamond films with controlled morphology on metal substrates. Electron emission spectra were recorded to 500°C, while illuminated with sub diamond band gap light. Significant photo-induced emission was observed with an efficiency greater than metal photo cathodes.

• Periodical: Advances in Science and Technology (Volume 95)
• Pages: 1-10
• DOI: https://doi.org/10.4028/www.scientific.net/AST.95.1
• Online since: October 2014
• Authors: Tian Yin Sun*, Franz A.M. Koeck, Robert J. Nemanich
• Keywords: Diamond, Negative Electron Affinity, Photo-Induced Emission, Thermionic Emission

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