Growth of delafossite CuAlO₂ single crystals in a reactive crucible

Abstract

Delafossite oxide CuAlO2 has received great attention as a promising p-type conducting oxide. In this work, high-quality CuAlO2 single crystals with a size of several millimeters (mm) are successfully synthesized with a reactive crucible melting method. The crystals are characterized by X-ray diffraction, scanning electron microscopy with energy-dispersive spectroscopy, transport measurement, and magnetic susceptibility measurement. The CuAlO2 single crystals show semiconducting behavior with hole carriers, which is consistent with other crystals grown by the conventional slow-cooling method. This growth method we reported here eliminates the process of removing the remaining flux, allowing easy access to the high-quality single crystals. This new approach to growing high-quality delafossite oxide CuAlO2 with a few mm size is important for new technologies that demand p-type semiconductor-based device fabrication.

Theoretical Investigation of Delafossite-Cu2ZnSnO4 as a Promising Photovoltaic Absorber

“…Rather, the XRD pattern can be interpreted with four stable binary and ternary compounds: Zn 2 SnO 4 , SnO 2 , Cu 2 O, and CuO. The XRD peak intensities of Cu 2 O and CuO are relatively weaker than those of Zn 2 SnO 4 and SnO 2 , which might be attributed to the volatile nature of Cu atoms and the reaction between Cu x O and the alumina crucible [26]. This result indicates that the precise control of stoichiometry (particularly the amount of Cu atoms) is crucial for synthesizing CZTO.…”