In situ observation of reflection high-energy electron diffraction during the initial growth of SiC on Si using dimethylsilane

Abstract

Initial growth stage in heteroepitaxy of 3C-SiC on Si (0 0 1) surface was studied in situ by reflection high-energy electron diffraction (RHEED) using dimethylsilane (DMS) as a source gas at 650–1050°C. After the supply of DMS, Si (2×1) structure changed to a mixture of Si (2×1) and Si c(4×4) structures at 650–750°C. After an incubation time, 3C-SiC spots were observed. In the case of DMS supply before raising the substrate temperature, three different RHEED patterns were observed, i.e. 3C-SiC spots after incubation time (650–700°C), 3C-SiC spots with streaks related to twin (750–900°C) and 3C-SiC spots with ring patterns (1000–1050°C) without incubation time. The initial growth rate of SiC was evaluated from the variation in the time between the appearance of SiC spots and the disappearance of the Si (2×1) structure at 650–750°C.