Near UV and Visible Region Photoluminescence Curves Study for AlN Thin Film and AlN Nanopowder

Abstract

Well dispersed Aluminum Nitride (AlN) nanopowder and AlN thin film were compared to observe their structural and luminescence properties. AlN thin films were deposited on silicon and copper substrates by RF magnetron sputtering. PL peaks analysis indicated the same pattern of emission peaks over different excitation wavelengths ranging from 200 nm to 300 nm for both the AlN nanopowder and thin film, nearly 100 -1000 times PL increment observed in AlN nanopowder. It is suggested that the reason for PL of AlN material is due to surface defects and impurities like oxygen-related point defects (O+N), nitrogen vacancies (VN), the transition from the donor level of VN (nitrogen-vacancy) to the acceptor level of AlN (antisites defects), and various defect complexes (V3-Al – 3 O+N) are responsible for the enhanced observed emission peaks. With well-defined emission curves, AlN Nanopowder and thin films are observed to be good substrate and insulator material for microelectronic circuits, Light Emitting Diodes, Laser Diodes, and in biomedical applications such as bioimaging and biosensors.