Computer Analysis of Surface Recombination Process at Si and Compound Semiconductor Surfaces and Behavior of Surface Recombination Velocity

Abstract

A theoretical analysis of the surface recombination is performed for n-Si, GaAs and InP surfaces under photo-excitation in terms of the so-called effective surface recombination velocity Seff. A very strong dependence of Seff both on the excitation light intensity and the surface fixed charge density has been found. Seff reaches its maximum when ns≈ps, independently on the light intensity. Seff can be significantly reduced by shift of the surface Fermi level towards band edges by means of the surface fixed charge QFC or by appropriately reducing or reshaping the surface state density distribution.