Co-reporter:Weiyuan Duan, Yu Qiu, Liping Zhang, Jian Yu, Jiantao Bian, Zhengxin Liu
Materials Chemistry and Physics 2014 Volume 146(1–2) pp:141-145
Publication Date(Web):15 July 2014
DOI:10.1016/j.matchemphys.2014.03.012
•The influence of a-Si:H precursor dehydrogenation on AIC process was studied.•Dehydrogenation can improve microstructural quality of poly-Si thin films.•Smoother surface morphology can be observed on dehydrogenation samples after AIC.•The dehydrogenation process is necessary for fabricating high quality solar cells.Polycrystalline silicon (poly-Si) thin film grown on low cost substrates such as glass at low temperature is an attractive material for cost-effective solar cells. This work studied the influence of dehydrogenation of a-Si:H precursor on the crystallization behavior by aluminum induced crystallization (AIC) process below the eutectic temperature of 577 °C. The a-Si:H films were deposited by PECVD and aluminum was evaporated in a vacuum evaporation equipment, respectively. Some of the a-Si:H thin films were dehydrogenated in nitrogen atmosphere before aluminum evaporation. It was found that hydrogen content in a-Si:H drops to a stable value after annealing at 480 °C for 1 h. Micro-Raman spectroscopy, Fourier transform infrared spectroscopy, X-ray diffraction spectroscopy and scanning electron microscopy measurements were used to investigate the structural characteristics of the a-Si:H and the prepared poly-Si thin films. Our results show that although the dehydrogenation increases AIC temperature and reduces AIC rate, it can improve microstructural quality of poly-Si thin films, leading to less tensile stress, higher crystallinity, smoother and more conformal surface morphology.