Atomic-layer level control in SiC crystal growth using gas source molecular beam epitaxy was demonstrated. Alternate supply of source gases of Si2H6 and C2H2 induced the transitions of surface superstructures. When Si2H6 was supplied, Si atoms generated by thermal decomposition were adsorbed on a 3C-SiC (001) substrate, which brought about the change of surface superstructures from the initial c (2 × 2) to the sequential evolution of (2 × 1), (5 × 2) and (3 × 2) corresponding to the increase of constituent Si atoms. When C2H2 was supplied, the adsorbed Si atoms reacted with the C2H2 molecules, resulting in crystallization of SiC, and the superstructure showed the initial c(2×2) pattern. The growth rate seemed to be regulated by the limited number of Si atoms forming superstructures. Detailed analysis of in-situ dynamic RHEED observation revealed the proper configuration of surface superstructures, and the possibility of one-monolayer growth of 3C-SiC was discussed.
ASJC Scopus subject areas
- Condensed Matter Physics
- Surfaces, Coatings and Films
- Electrical and Electronic Engineering