The Preparation and Characterization of InP and Related III-V Single Crystals and Epitaxial Layers Produced by Molten Salt Electrolysis.

摘要

This report summarizes the results of a two-year investigation of the viability of electrodeposition as a means of preparing indium phosphide, ultimately for electronic device applications. InP proved to be a difficult material to prepare by this technique, mainly because of the restrictions imposed on the maximum temperature of deposition by decomposition of InP and volatilization of In2O3 solute. A major portion of the total effort was spent on finding an optimum solvent to meet the requirement that the maximum deposition temperature should not exceed 600 C, and the Na,K/PO3,F quaternary eutectic was found to give best results. Reproducible InP deposits of fairly uniform thickness were made onto (0001) single crystal CdS substrates at potentials of -0.90 to 1.00V (versus graphite) with current densities of 1-3mA/sq cm. In spite of these low current densities, deposits thicker than 1 micron were found to be polycrystalline. The purity of the deposits was not sufficiently high for device applications, but a marked improvement with length of deposition time was demonstrated. Deposits of InP on (111) InP substrates were also polycrystalline and of less uniform thickness.