Investigation of the deposition conditions on the microstructure of TiZrCuPd nano-glass thin films

Nano-grained metallic glass Ti-Zr-Cu-Pd thin films were deposited at room temperature on Si substrate by using direct current (DC) magnetron sputtering with an alloy target. The influence of the sputtering parameters like the DC power and sputtering pressure on the chemical composition and the microstructure of the deposited films was analyzed. Experiments were carried out by changing the sputtering pressure (from 0.2 to 0.8 Pa) and the sputtering power used was 100 or 200 W. The compositional variation with sputtering pressure and applied power was found to be due to the dissipation of the kinetic energy of the sputtered atoms by the interatomic collision. Microstructural studies of the as-deposited thin films by X-ray diffraction and high-resolution transmission electron microscopy (HRTEM) exhibited that the films have an amorphous structure. Nanometer-sized glassy clusters were observed in the thin films deposited at higher Ar pressure. Scanning electron microscopy (SEM) and atomic force microscopy (AFM) were used to study the surface morphology and topography of the Ti-Zr-Cu-Pd thin films. The as-deposited thin films exhibited granular morphology and its surface roughness was influenced by the Ar pressure. At low sputtering pressures, the surface morphology is characterized by low surface roughness. Moreover, the chemical composition and the size of glassy regions in the nano-glass thin films can be controlled by changing the sputtering parameters.