Thermal degradation of homoepitaxial GaAs interfaces

Abstract

Photoluminescence techniques have been used to detect and characterize p‐type conducting layers formed on the surface of semi‐insulating GaAs substrates and at the liquid phase epitaxial layer–GaAs substrate interface during pregrowth heat treatment. These layers contain ∼10¹⁷ cm⁻³ shallow acceptors and a high density of arsenic vacancy complexes, and can be eliminated by pregrowth Ga etching of the substrate.