IJM013 Effects of Partial Oxygen Content on Crystalline Structure and Surface Topography of Nanostructured Al2O3 Thin Films Prepared by DC Reactive Sputtering Technique

Abstract

Aluminum oxide thin films were prepared by dc reactive sputtering technique using different mixing ratios of argon and oxygen gases (90:10, 70:30, 50:50, 30:70, and 10:90). These films were characterized to introduce their crystalline structures, surface morphology, and elemental composition. A progressive transition occurs from a predominantly amorphous to a highly crystalline Al₂O₃ film as the oxygen content in the Ar:O₂ gas mixture is increased. Increasing the oxygen content leads to a progressive decrease in surface roughness, resulting in smoother and more uniform films with finer granular features. The oxygen-rich environments yield the smoothest surfaces, while argon-rich environments result in significantly rougher surfaces. These findings are critical for optimizing the sputtering process to achieve desired surface properties for various applications, as surface roughness profoundly impacts adhesion, optical properties, and device performance.