Screening and level broadening in inversion layers with random fixed charges

Abstract

The effects of potential fluctuations caused by randomly spaced fixed charges near a semiconductor-insulator interface on the density of states and the screening constant in an inversion layer are considered in a self-consistent, low-temperature, linear, long-wavelength, static screening approximation. The magnitude of the band broadening effects is calculated in this approximation for n-type inversion layers in Si. At low carrier concentrations, the screening constant and the density of states go to zero smoothly and at high carrier concentrations they approach the values expected for an ideal two-dimensional system. © 1976.