Abstract
Plasma CVD silicon nitride films are produced from SiH4–N2 gas mixture with a constant flow ratio SiH4/N2=0.1. When the pressure decreases and the substrate temperature increases, the Si/N composition approaches the stoichiometric value 0.75. As compared with the film deposited from SiH4–NH3 reaction, the present ammonia-free silicon nitride contains little N–H bonds and less hydrogen, and can be expected to have higher atom concentration and tight bondings.