The magnetic properties and characterization of Co1−x−yCryCx films produced by pulsed laser deposition

Nanogranular cobalt–chromium–carbon thin films have been fabricated by pulsed-laser deposition on glass substrates at different temperatures. The structural characterization and magnetic properties of these films were investigated. The transmission electron microscope images with selected area diffraction and X-ray diffraction showed that the as-prepared films consist of cobalt grains, Co3C phase, a small amount of Cr, and carbon. The hexagonal close-packed or face centered cubic cobalt nanograins with average size less than 20 nm, were separated by graphite-like or amorphous carbon. It was found that the coercivity and saturation magnetization of the films were highly dependent on the substrate temperature and carbon concentration. At room temperature the films have a maximum in-plane coercivity of 718 Oe and a maximum out-of-plane coercivity of 485 Oe, indicating a possibility of fabricating adjustable high coercivity cobalt–carbon based materials.