Liquid Phase Epitaxial Growth of Semi‐insulating GaAs Crystals

Abstract

Semi‐insulating crystals were grown by liquid phase epitaxy from a Ga solution doped with Cr metal. The room temperature resistivity of the layers was , depending on the doping concentration of Cr, the background donor concenetration, arsenic vapor pressure, and the cooling rate. It was found that the grown layers became semi‐insulating only when the background donor concentration of the undoped layer is lower than . Higher arsenic vapor pressure and the higher cooling rate give layers with higher resistivity. The threshold voltage, at which the curve changes from linear to dependence, varies with the square of the thickness with electron injecting contacts. The activation energy obtained from the temperature dependence of resistivity increases as the room temperature resistivity increases. The highest obtained was 0.71 eV.