Si and Sn Doping in Al_xGa_1-xAs Grown by MBE

Abstract

Electrical properties of Si and Sn doped Al x Ga 1- x As epitaxial films grown by MBE have been studied in the wide range of AlAs mole fraction. With a constant doping level, decrease in the carrier concentration was observed around the direct-indirect band crossover point, for Si-doped and Sn-doped Al x Ga 1- x As. Abrupt increase in donor ionization energy E D occurred in Si-doped Al x Ga 1- x As films. These characteristics are similar to those reported for Te and Sn doped Al x Ga 1- x As grown by LPE.