Stability, transparency, and conductivity of MgxZn1−xO and CdxZn1−xO: Designing optimum transparency conductive oxides

The stability, transparency, and conductivity of ZnO are suggested to be tailored by alloying with MgO or CdO to meet wide applications. Our Monte Carlo simulation based on first-principle cluster expansion methods partially explain the solubility and stability data scattered in extensive experiments and further reveal that CdxZn1−xO has much higher solubility than prevalent MgxZn1−xO in a large range of experimentally achievable temperature (400 K–1200 K). Furthermore, first-principles calculations based on hybrid functional methods show that CdxZn1−xO has better n-type doping properties than MgxZn1−xO. The optical gap of CdxZn1−xO could be ∼1.5 eV higher than its fundamental gap due to large Moss-Burstein shift. We thus predict that CdxZn1−xO has great potential to be a better transparent conducting oxide than MgxZn1−xO.