Analysis of chemical reactions showed that In-rich Cu(Ga,In)Se2 bulk crystals could be grown from melts by using the horizontal Bridgman method. Here, In-rich solid solutions were grown by using the above method, while controlling the Se vapor pressure between 20 and 500Torr, based upon the temperature-dependence of the Cu(Ga,In)Se2 phase diagram. These products were shown, by X-ray diffraction, to have a single chalcopyrite phase. Bulk single crystals with good crystalline quality could be grown under Se vapor pressures from 80 to 250Torr. The electrical and optical properties of the intrinsic defects were investigated by annealing samples in vacuum or Se atmospheres. Acceptors having activation energies of about 20, 35 and 140meV were attributed to Cu-vacancies, Cu in the III site and III-vacancies, respectively. Donors having activation energies of about 35, and 70 to 80meV, were attributed to 2 different kinds of Se-vacancy.

Single Crystal Growth of Cu(Ga,In)Se2 Solid Solutions by Horizontal Bridgman Method with Controlling Se Vapor Pressure and Their Defect Properties. H.Matsushita, K.Mitake, T.Takizawa: Journal of Crystal Growth, 2005, 275[1-2], e445-50