LPE growth of undoped n-type GaAs at 636°C with extremely low compensation

Abstract

Distinct growth-temperature dependence in the range of 636–795°C has been clarified in the concentrations of donor and acceptor impurities for the liquid-phase epitaxial GaAs materials grown after little solution-bakeout. To estimate the impurity concentrations correctly, photoluminescence evaluation was employed in addition to Hall measurement. At the lowest growth temperature and without solution-bakeout, the compensation ratio, N a /N d , is as low as 10 −3 . With baking at 800°C or below, the layer is still n-type despite the compensation by carbon acceptors. However, baking at 900°C or above is so influential that the epilayer is rapidly compensated by silicon acceptors. The slow growth at 636°C is effective to obtain n-type GaAs layers with extremely low compensation.