A fundamental study of the effects of grain boundaries on performance of poly-crystalline thin film CdTe solar cells

Poly-crystalline CdTe-based thin film photovoltaic devices have shown a great potential and are commercially used for large-scale energy conversion applications. Despite this success conversion efficiency of CdTe has achieved very minor improvements over the last 20 years. To overcome this stagnation and further drive cost-per-watt of the modules, better atomic-scale understanding of native dislocation structures and grain boundaries is needed. In this collaborative study we systematically investigate effects of grain boundaries using ultra-high-vacuum bonded CdTe bi-crystals with pre-defined misorientation angles.