Well-adhered hydrogenated amorphous carbon thin films on ferrous alloy using silicon-containing interlayers at low temperatures

Si-containing interlayers are commonly used to overcome the low adhesion of DLC films to steel. However, a relatively high deposition temperature of 300 ? is necessary to deposit interlayers that ensure adhesion when tetramethylsilane is used as precursor. Moreover, oxygen impairs the adhesion between thin films and ferrous alloys. This work aims to verify the influence of low background pressure in the deposition of a-SiCx:H interlayers using tetramethylsilane at low deposition temperatures. Also, this letter contains a systematic study of the physicochemical properties of the interlayer and its influence on the film's structure. The results show that a background pressure of 0.8 Pa suits the formation of well-adhered a-C:H thin films even at temperatures as low as 85 ?. Chemical analysis associates this outstanding increase in adhesion with fewer oxygen found within the interlayer and at both interfaces when compared to previous results at high background pressures.