Electron transport and emission properties of C(100)

Abstract

Secondary-electron-emission spectroscopy is used to probe the transport and emission of impact-ionized electrons in single-crystal diamond. By studying the emission from a cesiated C(100) surface having a negative electron affinity (NEA), the full energy spectrum of the internal electrons is revealed in the measured energy distribution data. The kinetic energy of the electrons and the height of the surface energy barrier are measured relative to the conduction-band minimum ${E}_{c},$ which is identified in the spectra. The cesiated diamond surface is observed to be NEA, but the hydrogenated diamond surface (commonly believed to be NEA) has an electron affinity near zero and slightly positive. Analysis of the very high yield data $({\ensuremath{\delta}}_{\mathrm{max}}\ensuremath{\sim}132)$ and the sharply peaked energy distribution data indicates that the transport of low-energy electrons is very efficient in C(100). An emission model is deduced that involves the surface properties of the material and the internal energy distribution of the electrons.