C Stability in Si1-yCy Epitaxial Films Grown by Low-Temperature Chemical Vapor Deposition

Abstract

Thermal stability of the substitutional C (Csub) in the Si1-yCy film has been investigated. The Si1-yCy films were grown on Si(001) substrates by low-temperature plasma-enhanced chemical vapor deposition using SiH4 and H2. C2H2 or SiH2(CH3)2 were used as C source gases. The simulation taking into account the chemical reactions of the complexes of the Si–C–H system in the Si1-yCy well explained the annealing behavior and thermal stability of the Si1-yCy films. During high-temperature annealing, thermal diffusion of Csub occurred resulting in 3C-SiC precipitation. The activation energy for the precipitation was estimated at 3.18–3.23 eV from the simulation. Both the calculated and experimental results showed that thermal stability of the Si1-yCy decreased with increasing initial Csub content in the film.