Mechanism of low temperature growth of Al-induced polycrystalline Si film

The growth of Al-induced polycrystalline silicon films at a low temperature (≤577°C) was physically modeled, analytically simulatd, and experimentally evaluated, basde on Gibbs free energy description of the second law of thermodynamics. The Al-induced laver exchange mechanism was found to explain fairly well the dynamic process of the amorphous Si atoms, diffused through the Al2O3 buffer layer into the Al layer. The impacts of the annealing temperature of the poly-Si and the growth condition of the Al2O3 buffer layer on the time evolution of Si content in the Al2O3 buffer layer before its nucleation, and the variations in the Si nucleation time were calculated. The porous depth of the Al-induced poly-Si films, annealed at different temperatures, were characterized with transmission electron microscopy to test the simulated results; and the activation energy of a-Si dissolved into Al was calculated to be 0.75 eV.