On the Solid phase crystallization for thin film silicon solar cells on glass

Abstract

Polycrystalline silicon (poly-Si) thin film solar cells have potential for low cost photovoltaic (PV) applications. Poly-Si can be formed via the solid phase crystallisation (SPC) process, where a precursor layer of amorphous silicon (a-Si:H) undergoes a phase transformation to the crystalline form during prolonged annealing at temperatures >550 oC. The SPC process is not well understood, resulting in high dislocation densities in poly-Si resulting in electrical losses in PV devices. With focus on the materials properties, we gain an enhanced understanding of the correlation between the a-Si:H structure and the SPC dynamics on the final grain morphology and the nature of defects in the resulting poly-Si. This improved understanding of the SPC process will allow fabrication of more efficient poly-Si thin film PV devices.