THE EFFECT OF SURFACE NUCLEATION ON THE EVOLUTION OF CRYSTALLINE MICROSTRUCTURE DURING SOLID PHASE CRYSTALLIZATION OF AMORPHOUS SI FILMS ON SIO2

The effect of surface nucleation on the evolution of crystalline microstructure during the solid phase crystallization (SPC) of an amorphous Si (a-Si) film, deposited by low pressure chemical vapor deposition (LPCVD) on SiO2, has been investigated. The surface nucleation phenomenon was observed by suppressing the interface (a-Si/SiO2) nucleation by the incorporation of oxygen atoms during the initial deposition period of a-Si. It was found that the surface-nucleated polycrystalline Si (poly-Si) had equiaxial grains with the size of about 3–5 μm, while interface-nucleated one had elliptical grains with the size of about 0.3–1 μm.