Gallium phosphide doped with zinc - in current of inert gas contg. phosphine to prevent loss of phosphorus from substrate

摘要

Single crystal discs of gallium phosphide are doped in a diffusion vessel using a double protective atmos. in the hot zone of a diffusion furnace; and the total diffusion appts. forms a quasi-open system. The protective atmos. in the outer chamber is pref. nitrogen, flowing at 0.5 l/min.; and argon contg. 1-5 vol.% PH3; flowing at 0.35 l/min. through the diffusion chamber and into the outer chamber. The hot zone of the furnace is pref. at 830 degrees C. A simple process of doping GaP with Zn, where the partial pressure of phosphorous in the diffusion chamber, due to the decompsn. of the PH3, prevents the loss of phosphorous from the surface of the disc.