As in many polycrystalline materials, the physical and chemical properties of 3C-SiC coatings are dependent on the crystalline orientation. It has been shown that the Vickers microhardness of <111>-oriented 3C-SiC films, i.e. films in which the (111) planes were aligned parallel to the surface, was higher than those <110>-oriented . The (110) and (111) planes are the two planes in 3C-SiC with the lowest surface energy; 3.4 J/m 2 and 4.2 J/m 2 , respectively . In the SiCl4-based 3C-SiC CVD processes, the preferred growth orientation of resultant coatings varies with the selection of hydrocarbons as well as the deposition conditions. It was reported that using CH4 as carbon source, highly <111>-oriented 3C-SiC can be produced either at T = 1200 ℃, ptot = 4 kPa or at 1200 < T ≤ 1500 ℃, ptot ≥ 40 kPa 8 . On the other hand, at T= 1450 ℃, ptot = 1 kPa or at T > 1450 ℃, ptot ≤ 10 kPa, highly <110>-oriented 3C-SiC was obtained . Similarly, with C3H8 as carbon source, the growth at T = 1200 ℃, ptot = 4 kPa, was highly <111>-oriented, but switches to <110> at elevated temperatures . No explanation for these changes in preferred growth orientation was suggested in these studies.