Journal of Crystal Growth, Vol.385, 111-114, 2014
Lattice-matching of Si grown on 6H-SiC(000-1) C-face
Si films with < 111 > preferred orientation have been prepared on 6H-SiC(000 - 1) C-face. HRTEM and SAED results indicate that the Si film has cpitaxial connection with the 6H-SiC substrate and the parallel-plane relationship of the Si/6H-SiC heterostructure is (111)(Si)//(000 - 1)(6H-SiC). Using fast Fourier transform and Fourier mask filtering technique, misfit dislocations are clearly observed at the Si/6H-SiC interface, which accommodate the most of lattice mismatch strain. Every four Si (111) lattice planes are registered with five 6H-SiC(000 - 1) lattice planes along the interface. Based on the 4:5 lattice matching mode, the lattice structure of the Si/6H-SiC interface and its stability were energetically investigated by molecular dynamics simulations. When the Si films grow preferentially along < 111 > orientation on 6H-SiC (000 - 1) C-face, the misfit strain in Si layer significantly reduces due to the relaxation of C atoms in SiC layer near the Si/6H-SiC interface, and thus the Si/6H-SiC heterostructure has a stable interface with a small interface formation energy of -14.24 eV. (C) 2013 Elsevier B.V. All rights reserved.
Keywords:Crystal structure;Interfaces;Chemical vapor deposition processes;Semiconducting silicon compounds;Heterostructure semiconductor devices