Amorphous hydrocarbon films containing low chromium content was deposited on silicon wafer by a hybrid beams consisting of a DC magnetron sputtering and a linear ion source.Chmmiurn concentration in the films was controlled by varying the Ar/CH4 ratio in the supplying gas.During the deposition,a substrate bias of-100V was applied in all process.The structure and mechanical properties of the films were researched by EDS,Raman spectrum,XPS and nano-indentation as a function of Ar/CH4 ratio.The surface morphology and wettability were also investigated by AFM and contact angle tester,respectively.Chromium concentration determined by EDS and XPS in the film was not higher than 0.3 at.% and increased with Ar/CH4 ratio increasing.Carbide atomic band was not observed by XPS in all Cr-C:H films.The result of Raman spectra shows that sp3/sp2 ratio had a dramatic initial reduction due to the chromium addition.However,it subsequent increased as the Ar fraction increased in the gas flux.The hardness and elastic modulus of the films exhibited similar behavior with the ratio of sp3/sp2 as a function of Ar/CH4 ratio.It implied that the mechanical properties of Cr-DLC films were mainly dependent on the atomic bond structure of carbon.The roughness of the films charactered by AFM decreased owing to incorporate Cr atom.It shows that contact angle had a significant relationship with the roughness of the deposition films.