Effect of Al composition and V/III ratio of AlGaN on GaN for distributed Bragg reflector

In this study, we have deposited the AlGaN thin films for distributdd Bragg reflector (DBR). We investigated effects of Al content (18.0% ~ 47.2%) and III/V ratio (1437 4792) on AlGaN thin film. We analyzed image of grown AlGaN epi-layer by FE-SEM. There are different growth behaviors depending on III/V ratio under the greatest Al contents. Therefore, we optimized the AlGaN epi-layer growth conditions that have the highest Al content and adjusted III/V ratio. Also, AlGaN thin films were analyzed. Finally, we fabricated DBR using optimized AlGaN epi-layer and characterized the optical properties and surface morphology.