Grain size effect on noise properties in CoCrTa thin film media

Grain growth of Cr and CoCrTa thin film was examined using high resolution transmission electron microscopy (HRTEM) and high resolution scanning microscopy (HRSEM). The effect of crystallography on media noise was studied. The grain size of the CoCrTa thin film increases with thickness and retains a bi-crystal structure over a range of Cr grain size. Media noise at a high recording density seems to increase with the grain size of Cr underlayer surface. This suggests that the micromagnetization process can be influenced by a bi-crystal structure of Co alloy films at their initial layers.