Interface Characterization of Single-Crystal CdTe Solar Cells With VOC > 950 mV

Advancing CdTe solar cell efficiency requires improving the open-circuit voltage $\rm{(V_{{\rm{OC}}})}$ above 900 mV. This requires long carrier lifetime, high hole density, and high-quality interfaces, where the interface recombination velocity is less than about 104 cm/s. Using CdTe single crystals as a model system, we report on CdTe/CdS electrical and structural interface properties in devices that produce open-circuit voltage exceeding 950 mV.