Screening criteria for high-performance p-type transparent conducting materials and their applications

To accelerate discovery of promising p-type transparent conducting materials (TCMs), a screening strategy is formulated based on calculable selection metrics of thermodynamic stability, wide gap, low hole effective mass, and p-type dopability. Using this screening strategy, we identified three best-of class p-type TCM candidates (CaTe, BaTe and BeS) with combination properties of good transparency, high carrier mobility, and excellent hole dopability. Based on ionization energy calculations, we have established a concise and reliable criterion for assessing p-type performance. It is concluded that BeS is readily accessible an intrinsic p-type TCM, while CaTe and BaTe requiring extrinsic doping. Defect calculations are performed for the three compounds, providing strong support for our results. Although the defect calculations indicate a lack of shallow hole-producing defects in CaTe and BaTe, they both would be promising p-type TCMs when introducing impurities such as Na and K acceptor dopants. BeS contains an acceptor-type defect with a low formation energy (Be vacancies), which is responsible for its intrinsic p-type behavior. This physically formulated screening strategy would motivate the exploration and design of other advanced functional materials, and our established criterion could be another route to identify the p/n-type behavior of materials.