High Resolution Electron Microscopy of thin Co-Cr films

Co-Cr thin films have been studied extensively as leading candidates for perpendicular recording media. The development of microstructure in this system has been reported by a number of investigators. These studies have revealed a general growth scenario in which a fine grained, randomly oriented "transition layer" forms first, followed by the development of columnar grains having their hcp c axes textured normal to the film plane. However, it has been found that such columns are not present in very thin (∽10 nm) layers. Also, it has been inferred from electron microdiffraction studies that both c and a axis texturing occurs in these same films. However, direct evidence for this texturing is still needed. In this work, high resolution electron microscopy (HREM) has been employed to examine very thin (5-10 nm) Co-Cr layers.