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Liquid Polycarbosilane derived β-SiC and α-SiC coating was deposited at three differently moderate high temperatures by CVD method on Silicon wafers. The nano-mechanical properties such as hardness, reduced Young's modulus, elastic recovery and plasticity index of the coatings were evaluated and compared at different deposition temperature. It was observed that with the increase in deposition temperature the nano-mechanical property of the coating enhances, the reason being the increase in crystallinity along with good adherence at higher temperature. Moreover the tribological properties of the coated samples show similar trends with increase in deposition temperature although it were found to be much better for the β-SiC than that of the α-SiC coated samples. All the coated samples shows brittle mode of failure during tribological testing. It was found that the 900 °C deposited film has better nano-mechanical as well as good tribological properties compared to other temperature of deposition due to better crystallinity and adherence. Thus the enhanced mechanical and tribological properties of this coating can be used as protective films on silicon for application in micrometers and other micro devices.

Silicon carbide coating on silicon (1 1 1) wafer was deposited by modified chemical vapor deposition (CVD) method using liquid polycarbosilane (LPCS) as precursor at three different moderately high temperatures in presence of Argon gas. Glancing angle X-ray diffractometer and Fourier Transform Infrared Spectroscopy reveals smooth β-SiC coating and its subsequent transformation into α-SiC on silicon substrate. In all the temperature the film was found to be uniform with a thickness ranging from 0.6–1.2 μm. The average particle size as can be seen from FESEM ranges from 7 to 385 nm approximately, the lowest range being (7–20 nm) which hitherto has not yet been reported using LPCS as precursor for SiC. Moreover the coated samples show substantial increment of hardness (∼18.8 GPa) and toughness (∼1.51 MPa m 1/2 ), both of which increases with increase in deposition temperature. The smooth and thin SiC coating on silicon formed in three different moderate temperatures compared to very high temperature for other CVD assisted coating along with enhanced hardness and toughness makes this a promising material in critically harsh environment required for microelectromechanical systems (MEMS) application.