INVESTIGATION OF HETEROSTRUCTURES 3C-SIC/15R-SIC

Abstract

The subject of study. Investigation results for 3C-SiC layers, obtained on single-crystal 15R-SiC substrates by sublimation epitaxy in vacuum are presented. Materials and methods. 15R polytype Lely crystals were used as a substrate; the growth was carried out on polar С (000 )1 and Si (0001) substrate faces. The growth temperature was 1950-2000 °C, and growth time was equal to 10 min. Commercial silicon carbide powder with a grain diameter equal to 10-20 µm was used as a growth source. The following methods were applied for the characterization of grown epitaxial layers: cathodoluminescence, optical microscopy and two-crystal X-ray diffraction. Main results. The possibility of obtaining epitaxial 3C-SiC on 15R-SiC substrate by sublimation epitaxy in vacuum was demonstrated. It is shown that, C-face is preferable for heteropolytype growth, since more uniform growth of cubic polytype is observed on it with a small percentage of spurious substrate polytype inclusions; the same situation appears in the case of 6H-SiC substrate application. Practical significance. Comparison of the results of heteropolytype growth for 3C-SiC on substrates of other polytypes (6HSiC, 15R-SiC, 4H-SiC) will give the possibility to understand more completely the transformation mechanism of the crystal lattice during epitaxial growth and to develop a theoretical model of the process.

Keywords

• silicon carbide
• sublimation epitaxy
• cathodoluminescence
• X-ray diffractometry