3C-SiC Single-Crystal Films Grown on 6-Inch Si Substrates

Abstract

The heteroepitaxial growth of 3C-SiC on Si(001) substrates has been studied in a hot-wall-type low-pressure reactor. The Si substrates were carbonized by C2H2 prior to the SiC growth process to suppress the undesirable effects of lattice mismatching between Si and 3C-SiC. A single-crystal carbonized layer (3C-SiC) was obtained from 500 °C to higher than 1000 °C in an C2H2 environment. Following the carbonization process, SiH2Cl2 and C2H2 were alternately supplied into the reaction tube to grow an epitaxial 3C-SiC film. The growth rate of 3C-SiC depended on the amount of Si incorporated into the surface of the substrates by H2 reduction of SiCl2 as a Si precursor. The “H2 intermittent flow” method employed during the SiC growth process efficiently suppressed the reduction of SiCl2 and induced a constant growth rate of the SiC. The crystallinity of the grown 3C-SiC films on Si substrates was evaluated using transmission electron microscopy, selected-area electron diffraction, and X-ray diffraction methods. The grown 3C-SiC films included anti-phase boundaries and twins. The concentration of these plane defects decreased due to coalescence with each other during SiC growth and resulted in an improvement in crystallinity and electrical properties.