Nanometric multilayered structures were deposited by PECVD. Deposition on the cathode resulted in amorphous multilayers (a-C/a-SiC/.../a-SiC and a-C/a-SiN/.../a-SiN), whereas nanostructured multilayers (ns-Si/ns-SiC/.../ns-Si) were obtained at the anode. Previous studies on multilayer structures of ns-Si/ns-SiC deposited at room temperature on c-Si wafers by modulated PECVD revealed the mechanical and wear characteristics of these structures, which showed improved adherence to the substrate and blocking of the cracks induced by nanoindentation. Another characteristic of these structures was the absence of oxygen in the SiC layers after exposure to the atmosphere. In the present study, the mechanical characterization of the nanometric multilayer ns-Si/ns-SiC structures, after annealing under an inert atmosphere, has shown an increase in hardness due to: (a) material densification, with an increase in density after dehydrogenation; and (b) crystallization of the layers. Although the films were deposited at low temperature, the need to anneal them to improve their mechanical properties requires the use of temperature-resistant substrates. To avoid the need for post-thermal treatments, we have chosen the deposition of nanometric multilayer structures of a-C/a-SiC and a-C/a-SiN (5-10 nm/layer) using PECVD at room temperature and depositing them on the cathode (higher ion bombardment). The microstructure and morphology of the hybrid amorphous layers were examined by TEM. Hardness and Young's modulus were measured by the nanoindentation technique. Wear properties were evaluated using a pin-on-disc system. The structures containing approximately 20 layers had better mechanical properties than the corresponding thick monolayers of their components. Their mechanical characteristics, along with their ability to block crack propagation and wear resistance, are useful for applications such as protective coatings for optical (fibers and lenses), electronic and magnetic devices.