a-SiC:H Films by Remote Hydrogen Microwave Plasma CVD From Ethylsilane Precursors

摘要

Amorphous, hydrogenated, silicon carbide (a-SiC:H) films are deposited in the remote hydrogen microwave plasma (RP-CVD) process using diethylsilane as a single-source precursor. The effect of substrate temperature (T_S) on the kinetics of RP-CVD, chemical composition, structure, surface morphology, and properties (density, refractive index, and extinction coefficient) of the resulting a-SiC:H films is investigated. The T_S dependence of film growth rate implies that RP-CVD is an adsorption-controlled process. The increase of T_S from 30 °C to 350 °C causes the elimination of organic moieties from the film and the formation of a Si-C network structure. The relationships between the content of Si-C bonds, represented by the relative integrated intensity of the Si-C IR band, and the film properties are determined. The number of Si-C bonds is found to be a key parameter in the control of the examined film properties. The films deposited at T_S = 350 °C appear to be very dense materials exhibiting small surface roughness and high refractive index. The results of the present study are compared with those reported for a-SiC:H films produced by RP-CVD from a triethylsilane precursor.