This paper addresses the doping mechanism of amorphous semiconductors through the investigation of boron doped rf co-sputtered amorphous hydrogenated silicon. The activation energy and room temperature conductivity varied from 0.9 to 0.3 eV and from 10-12 to 10-4 Ohm-1 .cm-1, respectively, by ranging the boron concentration from 0 to 3 at.%. These ranges of electronic properties are of the same order of those reported for samples prepared by plasma enhanced chemical vapor deposition (PECVD). In spite of these similarities, there are some relevant differences. The doping effciency, at low boron concentrations, is much lower than that of PECVD samples. In addition, the creation of deep defects (dangling bonds) does not follow the square root power law dependence on the boron concentration as proposed by Street and observed in PECVD samples. These differences are associated with the density of defects, which is much higher in films prepared by sputtering. The increase in the deep defect density is more likely related to topological disorder, introduced by the presence of a high concentration of inactive impurities.

TiCxNy coatings deposited on high-speed steel substrates have been used to enhance the tribological properties of cutting tools (hardness, wear resistance, etc.) as well as their corrosion resistance in an aggressive environment. These layers are usually produced by plasma deposition techniques (PVD or CVD), and different coating properties can be obtained with each method. In this work, TiCxNy films were deposited on AISI M2 high-speed steel substrates by the reactive magnetron sputtering technique. A series of samples with a variety of reactive gas mixtures (nitrogen and methane), substrate biases, and deposition temperatures was produced. As a result, coatings with different chemical compositions were deposited for each group of deposition parameters. Gas mixture composition and substrate bias directly affected the chemical composition of the coating, while deposition temperature influenced the chemical composition of TiCxNy layers to a very low extent.