Nanostructure optimization of Zr-W-Ti metallic glass thin films via multitarget co-sputtering with oblique angle deposition approach

Abstract In this work, we systematically investigated the Zr-W-Ti nanostructured metallic glasses (NMGs) thin films on silicon (Si) wafer substrate fabricated via multitarget co-sputtering with oblique angle deposition (OAD) technique. By varying the substrate angles (θs) from 0° to 55°, the evolution of Zr-W-Ti NMGs from dense to nanocolumnar and nanorod film were observed by field-emission scanning electron microscope (FE-FEM), which created by the self-shadowing effect. The critical point of substrate angles was around 15° to produce the nanocolumnar and 40° to form the nanorod structure. The relationship among the substrate angles and the Zr-W-Ti NMGs tilted angle (β) was determined and discussed in detail with two theoretical correlations as the "Tangent rule" and "Cosine rule." The X-ray photoelectron spectroscopy (XPS) studied revealed the different chemical compositions. The results obtained from grazing incidence X-ray diffraction (GIXRD) and transmission electron microscope (TEM) indicated that the prepared Zr-W-Ti NMGs thin films exhibit an amorphous structure. Ultimately, it suggests that the multitarget co-sputtering with the OAD technique provides NMGs thin films, enabling applications in gas storage and sensor devices due to their well-defined nanostructured morphological and chemical composition characteristics.