Enhanced nano-mechanical and wear properties of polycarbosilane derived SiC coating on silicon

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.