Intrinsic defect engineering of cuprous oxide to enhance electrical transport properties for photovoltaic applications

Intrinsic point-defect species in cuprous oxide films are manipulated based on their thermodynamic properties via the implementation of a controlled annealing process. A wide range of electrical properties is demonstrated, with a window suitable for high-quality solar cell devices. A variation of carrier concentration over two orders of magnitude is demonstrated. Minority carrier lifetime is investigated by means of microwave photoconductance decay measurements, demonstrating a strong correlation with carrier concentration. Spectrally resolved photoluminescence yields are analyzed to provide insight into lifetime limiting mechanisms as a function of Cu2O processing parameters. Hall measurements of carrier mobility and concentration are taken at room temperature to provide insight into the effect of these processing conditions on net ionized defect concentration.