Vapour-liquid-solid mechanism for the growth of SiC homoepitaxial layers by VPE
Résumé
In order to reach fast growth regime, we have investigated the SiC homoepitaxial growth on off-axis 4H-SiC substrates from a vapour–liquid–solid (VLS) mechanism in a vertical cold wall CVD reactor. The experiments involved silane and propane diluted in hydrogen as feeding vapour phase and melted silicon as ‘‘liquid catalyst''. Growth rates up to 25 mm/h at 1500°C and 35 mm/h at 1600°C with a bunched step-terrace structure are demonstrated in such a system. The formation and stability of the VLS equilibrium is discussed with respect to the experimental parameters and a first approach of the mechanism is proposed.