Chemical vapor deposition condition dependence of reconstructed surfaces on 4H-SiC (0001), (000 1 ¯ ), and (1 1 ¯ 00) surfaces

Chemical vapor deposition has been developed to enable defect-free 4H-SiC crystals to be grown at lower cost and with higher growth rates. However, the structure and stability of 4H-SiC surfaces during crystal growth has not been clarified. In this study, we performed first-principles calculations and obtained the surface energies of ideal surfaces and Si-terminated surfaces on (0001), (000 1 ¯ ) and (1 1 ¯ 00) surfaces. For the (0001) and (000 1 ¯ ) surfaces, the Si-terminated surfaces are more stable than the ideal surfaces and Si atoms are adsorbed onto the surfaces up to high temperatures. The ideal surface on the (1 1 ¯ 00) surface is stable, and the Si-terminated surface changes to an ideal surface at lower temperatures than on the (0001) and (000 1 ¯ ) surfaces. These results indicate the possible temperature ranges in which to perform crystal growth. Thus, we clarified the conditions required to grow 4H-SiC crystals and the dependency of these structures on surface orientation.