Experimental Study of Structural Zone Model for Composite Thin Films in Magnetic Recording Media Application
Composite thin films are a new area of study with many applications, e.g. metal + oxide thin films in high density magnetic recording media. Engineering the processing, microstructure and properties of these thin films is of great importance. It has been found that microstructures of the thin films depend strongly on the oxide volume fraction and pressure during sputtering. Surface diffusion and self-shadowing effects are found to play important roles in determining various thin film microstructures under different processing conditions. Four characteristic microstructural zones could be generally distinguished: “percolated type”(A), “maze-like type”(T), “granular columnar type”(B) and “embedded type”- a microstructure with metal nanocrystals embedded in the amorphous matrix (C). This modified structural zone model of composite thin films has been proposed as a supplement to Thornton’s model for sputtered thin film system.