Measurement of GaAs surface oxide desorption temperatures

Abstract

Auger analysis of oxidized GaAs surfaces, heat treated in vacuo, has been used to establish an accurate value for the oxide desorption temperature Tox. Major differences are found in the value of Tox for the surface oxides produced by thermal and ozone oxidation: 582±1 °C and 638±1°C, respectively. These temperature differences are also confirmed by reflection high-energy electron diffraction observations of the thermal cleaning of GaAs substrates prior to epitaxial growth in a molecular beam epitaxy system. It is suggested that the measured temperatures can be used in establishing appropriate growth conditions for ‘‘indium-free’’ GaAs substrates during molecular beam epitaxial growth.