Polycrystalline Silicon Thin Film Formed By Multiple Pulsed Rapid Thermal Annealing – Intrinsic a-Si Film Thickness Effect

ABSTRACTThe polycrystalline n+/intrinsic silicon thin film stacks with various original intrinsic amorphous silicon layer thicknesses were formed using the multiple pulsed rapid thermal annealing process with the Ni-induced crystallization mechanism. The thick polycrystalline silicon stack was prepared by repeated steps of 1) amorphous silicon thin film deposition, 2) solution oxidation, 3) dehydrogenation, 4) pulsed rapid thermal annealing, and 5) oxide stripping. The poly-Si film properties, such as the grain size, orientation, and volume fraction of the crystalline phase, were related to the original intrinsic silicon film thickness and the total thermal budget. This process is effective in preparing the high volume fraction polycrystalline silicon thin film, which is important for low-cost thin-film solar cells, electronic and optoelectronic devices.