Polymerized hexamethyldisilazane coated on equiatomic TiNi shape memory alloy using DC-pulsed plasma assisted chemical vapor deposition

SiC:H organic-like thin films are deposited on Ti50Ni50 shape memory alloy by asymmetric bipolar DC-pulsed plasma assisted chemical vapor deposition (PACVD) in the gas mixture of hexamethyldisilazane (HMDSN) and Ar at room temperature. The deposition rate of the plasma-polymerized HMDSN (PPHMDSN) thin film is faster than that of RF process and the PPHMDSN thin films not only enhance the corrosion resistance but make the corrosion current density decay four orders. The surface morphology of the films is very smooth and uniform and the root mean square of surface roughness is in the range between 3 and 5 nm. The organic-like thin films containing peroxides or free radicals can be grafted with polymer acrylamide (AAm) which can improve the biocompatibility of TiNi shape memory alloy.