Abstract
A modified four-step method was applied to grow a 3C-SiC thin film of high quality on the off-axis 1.5° Si(111) substrate in a mixed gas of C 3 H 8 , SiH 4 and H 2 using low pressure chemical vapor deposition. The modified four-step method adds a diffusion step after the carburization step and removes the cooling from the traditional three-step method (clean, carburization, and growth). The X-ray intensity of the 3C-SiC(111) peak is enhanced from 5 × 10 4 counts/s (the modified three steps) to 1.1 × 10 5 counts/s (the modified four steps). The better crystal quality of 3C-SiC is confirmed by the X-ray rocking curves of 3C-SiC(111). 3C-SiC is epitaxially grown on Si(111) supported by the selected area electron diffraction patterns taken at the 3C-SiC/Si(111) interface. Some {111} stacking faults and twins appear inside the 3C-SiC, which may result from the stress induced in the 3C-SiC thin film due to lattice mismatch. The diffusion step plays roles in enhancing the formation of Si-C bonds and in reducing the void density at the 3C-SiC/Si(111) interface. © 2010 Elsevier B.V. All rights reserved.