Solubility and Electrical Behavior of Group IV Impurities in Solution Grown Gallium Phosphide

Gallium phosphide crystals doped with silicon, germanium, or tin were grown from solution by using a thermal gradient technique. At low doping levels nearly all of the tin or silicon atoms act as donors, i.e. , substitute on gallium sites. At higher doping levels the number of tin and silicon atoms substituting on phosphorus sites increases to about 30% and almost 50%, respectively. In contrast, doping with germanium yields p‐type material at the lower doping levels and n‐type material at higher doping levels with nearly equal numbers of germanium atoms on both sites at all doping levels.