Nanolayer coatings for hard disk and demanding tribological applications

Coating properties and performance can be tailor-designed by proper control of nanostructure and process conditions. This paper presents two examples: first, the synthesis and optimization of 1 nm thick nitrogenated carbon (CN_x) nano-layers as protective overcoats in extremely high density hard disk systems, and, second, the development of multilayer coatings for wear protection at elevated temperatures. Synthesis of these coatings was done by magnetron sputtering. These studies demonstrate that one can produce atomically smooth 1 nm thick CN_x overcoats with acceptable corrosion performance. In addition, this paper shows that, with the proper choice of nanolayer thickness and process conditions, superhard coatings based on TiN/SiN_x and TiB₂/TiC multilayers with high thermal stability, low internal stress, and high wear resistance can be synthesized.