COMPUTER-ANALYSIS OF SURFACE RECOMBINATION PROCESS AT SI AND COMPOUNDSEMICONDUCTOR SURFACES AND BEHAVIOR OF SURFACE RECOMBINATION VELOCITY

A theoretical analysis of the surface recombination is performed for n -Si, GaAs and InP surfaces under photo-excitation in terms of the so-c alled effective surface recombination velocity S-eff. A very strong de pendence of S-eff both on the excitation light intensity and the surfa ce fixed charge density has been found. S-eff reaches its maximum when n(s) approximate to p(s), independently on the light intensity. S-eff can be significantly reduced by shift of the surface Fermi level towa rds band edges by means of the surface fixed charge Q(FC) or by approp riately reducing or reshaping the surface state density distribution.