Method for control of si concentration in gallium phosphide single

Abstract

A method for controlling the Si concentration in a GaP single crystal layer grown in a series of runs of GaP liquid phase epitaxial growth with the repeated use of one and the same Ga solution, which comprise the steps of: measuring the Si concentrations of the GaP single crystal layers in preceding runs; then determining the additional Si amounts to be added into the Ga solution to refresh the Si effective concentration therein in reference to the Si concentrations in the layers; and adding Si of the thus determined amount into the Ga solution to commence the subsequent run, wherein the Si concentration in each of the GaP liquid phase epitaxial growth layers is determined from measurement of the O/G ratio in the layer, which is computed from each pair of the both values of the photoluminescent spectral peak intensity around the wavelength of 6300 .ANG. (O component) as the numerator and the other photoluminescent spectral peak intensity around the wavelength of 5540 .ANG. (G component) as the denominator in the photoluminescence spectrum obtained by illuminating the GaP liquid phase epitaxial growth layer with a laser beam at room temperature, with the help of good correlation therebetween.