DEEP CENTER SCATTERING POTENTIAL IN INGAP

Mobility limited by the scattering of a phosphorous vacancy-induced de ep center in In0.5Ga0.5P alloy grown by liquid-phase epitaxy on a (100 ) GaAs substrate has been investigated by means of Hall mobility and d eep-level transient spectroscopy measurements. Two kinds of scattering potentials, Gaussian well type and square-well type, were considered. It was found that the scattering potential can be better described by the Gaussian-type potential than the square-well one. The mobility li mited by deep center scattering has been fully calculated and analyzed . As a result, the mobility is characterized by a temperature dependen ce of T--1/2 in the temperature range from 77 to 400 K. The point defe ct scattering severely reduces the total mobility as its concentration increases. In addition, the scattering case when there is an electron trapped in the Gaussian potential well was also quantitatively invest igated. (C) 1994 American Institute of Physics.