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ZnSiAs2 (chalcopyrite structure) single crystals were grown by chemical vapor transport (CVT). Hall effect and photoelectrochemical techniques were used to characterize the properties of the p-type materials. Doping level, mobility, and resistivity were determined and compared with literature values for crystals obtained from other growth techniques. Photocurrent spectroscopy was used to measure the bandgap and transition types in the crystals. The interfacial energetics were measured with capacitance techniques (Mott−Schottky). The effect of various wet chemical etchants on the photocurrent voltage curves and quantum yields for carrier collection was also investigated.

Polarization dependent photoluminescence and photocurrent measurements were carried out on undoped and sulfur doped single crystals of CdSiAs2. For undoped crystal the interband transition A shows a 40 meV blueshift under perpendicular light polarization with respect to the parallel one. This shift is about twice as large for sulfur doped crystal. A pronounced photoabsorption band at 1.53 eV, related to the sulfur donor, is observed in the low temperature photocurrent spectrum. A significant enhancement of the optical anisotropy of donor-acceptor transition is seen in the low temperature photoluminescence spectra of CdSiAs2 doped with sulfur.