Relationship of microstructure properties to oxygen impurities in nanocrystalline silicon photovoltaic materials

摘要

We have fully investigated the correlation of microstructure properties and oxygen impurities in hydrogenated nanocrystalline silicon photovoltaic films. The achievement has been realized through a series of different hydrogen dilution ratio treatment by plasma enhanced chemical vapor deposition system. Raman scattering, x-ray diffraction, and ultraviolet-visible transmission techniques have been employed to characterize the physical structural characterization and to elucidate the structure evolution. The bonding configuration of the oxygen impurities was investigated by x-ray photoelectron spectroscopy and the Si-O stretching mode of infrared-transmission, indicating that the films were well oxidized in SiO_2 form. Based on the consistence between the proposed structure factor and the oxygen content, we have demonstrated that there are two dominant disordered structure regions closely related to the post-oxidation contamination: plate-like configuration and clustered microvoids.