Hall analysis of the electrical properties of n-type AlxGa1-xAs grown by MOVPE

Abstract

Variable temperature Hall measurements were used to study the electrical properties of undoped and Se-doped AlxGa1-xAs (0 <x < 0.4) layers grown by metalorganic vapour phase epitaxy (MOVPE). It is shown that the deep donor activation energy measured in undoped AlGaAs exhibits a similar dependency upon composition as that reported for Si-doped AlGaAs grown by MBE. For AlxGa1-xAs, doping with selenium is found to reduce the activation energy from 66 meV (forn = 4.1 x 1016/cm3), to 9 meV (forn= 1.6 × 1018/cm3).