Tribology of carbon nitride and boron nitride nanoperiod multilayer films and its application to nanoscale processing

Nanoperiod multilayer (CN/BN)n and (BN/CN)n films that have top CN and BN layers, respectively, were deposited by changing the top surface. The substrate was repeatedly positioned opposite the graphite and boron nitride semicircular targets. The hardness and wear depth of the 4-nm-period multilayer films were determined to be the highest and lowest, respectively, for all the sliding cycles. The hardness and wear resistance of (CN/BN)n films in which CN is the top layer are superior than those of the (BN/CN)n films. The weak top BN layer is easily fractured, and the wear rate of (BN/CN)n films is larger than that of (CN/BN)n films. Nanometer scale wear properties indicate that the wear resistance increased because of the prevention of fracture growth at the interface of each layer in the case of multilayer films. Nanometer scale mechanical processing of multilayer films by applying this layer-by-layer nanometer scale wear mechanism was realized.