High-quality polycrystalline silicon films with minority carrier lifetimes over 5 μs formed by flash lamp annealing of precursor amorphous silicon films prepared by catalytic chemical vapor deposition

Polycrystalline silicon (poly-Si) films with a thickness over I pm are formed by the flash lamp annealing (FLA), with a duration of less than 10 ms, of precursor amorphous silicon (a-Si) films prepared by catalytic chemical vapor deposition (Cat-CVD) on quartz substrates. Thicker a-Si films can be crystallized under lower lamp irradiance, which can be understood by considering both the total generated heat in the a-Si films and the thermal diffusion into the quartz substrates. Results of microwave photoconductivity decay (mu-PCD) measurement indicate that high-pressure water vapor annealing (HPWVA) is effective for improving the minority carrier lifetime of the poly-Si films. The film with a thickness of 1.5 mu m crystallized under a high lamp irradiance shows minority carrier lifetimes over 5 mu s, indicating the high feasibility of applying the crystalline film to high-efficiency thin-film solar cells.