Amorphous Silicon Core-shell Nanowire Solar Cells

Nanostructures such as nanoparticles and nanowires have been demonstrated as powerful tools to improve light absorption[1-4], to enable low temperature process[5], to demonstrate multi-exciton generation[6], and to decouple the absorption depth and carrier diffusion length[7, 8]. Here we demonstrated the first amorphous silicon coreshell nanowire solar cells, which can be fabricated through a low temperature, scalable processes. A simple Schottky based nanowire device structure is used to demonstrate the concept[9]. The device demonstrated much higher short circuit current (>150%) compared to the control thin film device, because of improved carrier collection. A coreshell nanowire solar cells based on p-i-n configuration is also proposed to further increase the efficiency. It provides a viable pathway to solve the mismatch between carrier diffusion length and absorption depth in amorphous silicon and to dramatically improve the device performance.