A throttle valve located between the chamber and the process pump regulated the pressure by adjusting its degree of opening. All 3C-SiC coatings in this study were prepared at a pressure of 10 kPa with a pC/pSi= 1 and a pH2/pSi= 23 in the gas phase, at temperatures between 1100 ℃ and 1350 ℃ for the C7H8 process and between 1100 ℃ and 1400 ℃ for the CH4 process.