Fractal growth of amorphous silicon crystallization induced by aluminum

Glass/Al(370nm)/Al 2 O 3 /a-Si(600nm) stack was prepared by radio frequency magnetron sputtering and naturally oxidation. The samples were annealed at 500؀ for 7 hours. After annealing, double-layered polycrystalline silicon (poly-Si) thin film was obtained. The upper layer is a continuous thin film and the lower layer consists of discontinuous dendritic crystalline grains. The fractal dimension of the dendritic crystalline grains is 1.86. Raman spectra show that the dendritic grain has high crystal quality close to single c-Si wafer.