Control of preferential orientation by in situ plasma supply during growth of polycrystalline silicon films.

Polycrystalline silicon (poly-Si) films were prepared on a fused quartz substrate at 700 °C by low-pressure chemical vapor deposition (LPCVD) and plasma-enhanced CVD (PECVD) using the same fabrication system. Poly-Si films with a strong <100> and <110> preferential orientation (P.O.) are obtained by changing the rf power for generating the plasma under the same preparation condition. The surface of the PECVD films with dominant <100> and <110> textures is very smooth in contrast with that of LPCVD films. These textures are maintained after thermal oxidation at 1000 °C, and the degree of P.O. and the grain size increase. [ABSTRACT FROM AUTHOR]