Papers by Keyword: XTEM

Abstract: We proposed a novel polishing technique named plasma assisted polishing (PAP) which combined atmospheric pressure water vapor plasma irradiation and soft abrasive polishing. Plasma irradiation oxidized the surface of workpiece and made it easier to be polished. PAP was applied to 4H-SiC, and an automatic flat surface without any scratches was obtained. In this study, we observed the processed surfaces using cross-sectional transmission electron microscopy (XTEM). The XTEM images showed us that an oxide layer with a thickness of about 20 nm was generated after plasma irradiation for 1 h, which proved the strong oxidation potential of OH radical in water vapor plasma. The surfaces processed by PAP were next observed, oxide layer was completely removed and no surface damages were introduced as the crystal structure of 4H-SiC was clearly observed and well ordered.

Abstract: By conducting a heteroepitaxy of a 3C-SiC film on a Si substrate and by annealing its surface in a UHV ambient, epitaxial graphene can be formed on such 3C-SiC virtual substrates. While the growth on the Si-terminated 3C-SiC(111)/Si (111) surface is known to proceed in a similar manner as on the Si-terminated 6H-SiC(0001) surface, successful growth of graphene on 3C-SiC(100)/Si (100) and 3C-SiC(110)/Si (110) surfaces remains puzzling. We have carried out detailed cross-sectional transmission-electron-microscopy observations on these systems to find out that (111)-facets may play crucial roles in the initiation of graphene on these surfaces. This observation also accounts for the absence of the interface layer at the graphene/SiC in these orientations.