Measurement of the mean electron-hole pair ionization energy in 4H SiC

Abstract

A measurement of the mean e-h pair creation energy ⟨Ee-h⟩ in SiC using a scanning electron microscope is presented. Uncertainties stemming from backscattering from high Z metal contacts, as well as from the semiconductor surface, are removed by explicit measurement through direct electron bombardment of the bare semiconductor surface. A reduced value of ⟨Ee-h⟩=5.05eV for 4H SiC is reported, which is significantly lower than previously reported values. Good correspondence with Monte Carlo simulations of impact ionization in 4H SiC was obtained.