Solid Phase Crystallization (SPC) of a-Si Thin Film Induced by a Novel Approach for Photovoltaic Devices

Abstract

The solid phase crystallization (SPC) of amorphous silicon thin films by a novel modification of nucleation step was investigated at low temperature.The thin film consists of polycrystalline nanoparticles embedded in an amorphous matrix which can act as nuclei, resulting in a lower thermal energy for the nucleation. Thus, this energy can shorten the transition time from amorphous to polycrystalline silicon and lower the processing temperature. The crystallinity and the crystallized volume fraction of silicon thin film annealed by the conventional furnace have been extensively studied by XRD and HRTEM. It was believed that high quality Si nanoparticles would act as nuclei for growth of crystalline Si, thus removing the high temperature requirement for nucleation. The crystalline films induced by nanoparticles can be used for the photovoltaic devices on glass substrates at a maximum temperature of 530°C.