Low-Temperature Growth of Polycrystalline Silicon Films bySiCl₄/H₂ rf Plasma Enhanced Chemical Vapor Deposition

Polycrystalline silicon film was directly fabricated at 200°C by the conventional plasma enhanced chemical vapor deposition method from SiCl₄ with H₂ dilution. The crystallization depends strongly on the deposition power. The maximum crystallinity and the crystalline grain size are over 80% and 200-500 nm, respectively. The results of energy dispersive spectroscopy and infrared spectroscopy measurements demonstrate that the film is mostly composed of silicon, without impurities such as Cl, N, C and bonded H. It is suggested that the crystallization at such a low temperature originates from the effects of chlorine, i.e., in-situ chemical etching, in-situ chemical cleaning, and the detachment of bonded H.