A comprehensive structural analysis of silicon carbide layers grown by vacuum epitaxy on silicon from hydrides and hydrocarbons
The phase composition, surface morphology and crystalline structure of carbon-containing silicon layers grown on silicon plates of various orientation by vacuum gas phase epitaxy using different operating conditions are considered. The possibility of phase transition from a Si1-xCx solid solution to silicon carbide upon annealing of the structures obtained by low-temperature epitaxy is discussed. The films were examined by the electron, probe and interference optical microscopy, electron diffractometry, and X-ray diffraction methods. The effect of germanium intercalated in a film during its growth on the surface morphology and crystalline structure of carbon-containing silicon layers is examined. Irrespective of the method of germanium insertion in the growing film, a maximum Ge concentration is attained at the interface of silicon and 3C-SiC layers. A comparative study of the surface roughness of 3C-SiC films grown on Si(100) was performed upon variation of the temperature and germanium content in a mixture of gases. The interference optical microscopy was used to investigate the surface morphology of heteroepitaxial structures 3С-SiC/Si in comparison with the surface characteristics of buffer structures based on Si and Ge. The 3C-SiC layers grown on Si(100) and Si(110) were shown to have quite a low surface roughness, which is comparable with the characteristics of Si1-хGeх/Si(100) layers and СР(Ge-Si1-хGeх)/Si(100) superlattices at the initial roughness of Si underlayers ~1-2 nm.