Boron Carbide and Boron-Carbon Nitride Films Deposited by DC-Magnetron Sputtering: Structural Characterization and Nanotribological Properties

Abstract

The effects of nitrogen incorporation into amorphous boron carbide (B4C) films were studied. The films were deposited by dc-magnetron sputtering with the Si substrates at room temperature. The nitrogen incorporation occurs at the expense of the boron content. The main feature of infrared absorption spectra obtained from B4C films is a broad band at around 1100 cm—1 that shifts to higher wavenumbers upon nitrogen incorporation. The spectra obtained from films with higher nitrogen content are typical of hexagonal boron nitride. The friction coefficient and the surface wear were studied by lateral force microscopy. The influence of several parameters like relative humidity, scanning velocity and load force was investigated. For boron–carbon nitride films, a weak dependence on the relative humidity of wear and friction coefficients was observed. In the case of B4C films, there is a clear correlation between the wear depth and the energy deposited at the AFM tip–film interface.