Influence of growth conditions on properties of InP homoepitaxial layers grown by liquid phase epitaxy

Abstract

Homoepitaxial layers of undoped InP were grown by liquid phase epitaxy in a vertical system using different equilibration temperatures and supercooling. The quality of the as-grown epilayers was assessed by the Hall effect and photoluminescence (PL) measurements. It is found that the layers exhibit a residual n-type conductivity and that the values of electron concentration and mobility vary throughout the thickness of a given epilayer. Moreover, the electron concentration is high with correspondingly low values of electron mobility in the first-to-grow regions of the epilayers. The PL measurements agree with the Hall data and show that the material quality is relatively poor when the layers are grown at a higher rate. On the basis of PL data, a window of processing parameters is identified where optimum luminescence properties are observed. The measured thicknesses of the epilayers are consistent with diffusion controlled mechanisms of epitaxial growth.