Magnetically enhanced plasma coating of nanostructures with ultrathin diamond-like carbon films

Diamond-like carbon (DLC) films are widely used as protective coatingsin a variety of technicalmacro- and micro-applications. However,most of the widely-used coating methods are not suitable for nanoscaleapplications. In this work, the method of magnetically enhancedplasma deposition (MEPCVD) was employed for the coating of AFMprobes and free-standing nanostructures with 3–20 nm thick DLCfilms. The carbon bonding structure, mechanical and tribologicalproperties of the films as well as the anisotropy of the coatings and itseffect on the shape of nanoscale features were investigated and it isshown that the method employed produces very smooth coatings(roughness below 0.2 nm) with a significantly lower than usual internalstress of 0.5–0.8 GPa. Wear tests of AFM probes at a high load (1 mN)showed that the DLC coating decreases their wear rate by two ordersof magnitude. It was found that coating of free-standing nanostructureseven with ultrathin DLC films may cause their deformationdue to the interface stress when the coating is asymmetric