Effect of hydrogen on the structure of high-rate deposited SiC on Si by atmospheric pressure plasma chemical vapor deposition using high-power-density condition

Using the atmospheric pressure plasma chemical vapor deposition (AP-PCVD) technique, SiC films were fabricated from the gas mixture of He, H-2, SiH4 and CH4 on silicon substrates. High-power-density condition was adopted to sufficiently activate the reactive gas molecules in the plasma. The structure, composition and crystallinity of the films were investigated as functions of the H-2 concentration in the gas mixture and substrate temperature. It was shown that increase in H-2 concentration in the plasma atmosphere reduced the growth temperature of polycrystalline SiC film. As a result, polycrystalline 3C-SiC film of which grain size was of the order of 10 run could be grown at a substrate temperature of 820 K with a deposition rate of approximately 6.7 nm/s. It was suggested that atomic hydrogen generated with addition of H-2 in the gas mixture considerably affects not only the reaction process at the film-growing surface but also the form of precursors in the atmospheric pressure plasma. The results indicated tile possibility of realizing the columnar growth of large 3C-SiC grains oil Si substrate when the H-2 concentration and the VHF power were simultaneously increased in tile AP-PCVD process. (c) 2005 Elsevier B.V. All rights reserved.