Effects of strain on crystallization of amorphous silicon characterized by laser Raman spectroscopy

Solid-phase crystallization at a surface of amorphous silicon and at an interface between amorphous silicon and a substrate was studied by laser Raman spectroscopy. Amorphous silicon was deposited on a fused silica substrate by a sputtering method. The thickness of the amorphous silicon film was about 3 pm. The samples were annealed at 700 or 1000°C. Amorphous silicon crystallized faster at the surface than at the interface. The results were confirmed by characterization of the cross section by micro Raman spectroscopy. It was found from Raman shift of the polycrystalline silicon that the effect of the strain is to suppress crystallization.