Dopant Concentration Dependent Room Temperature Ferromagnetism in Crystalline Sc Doped AlN Thin Films

In this study, high uniformity AlN thin films with varying Sc doping concentration levels were deposited on Ti (120 nm)/Si substrates. The impact of Sc doping ratio and annealing temperature on the magnetic properties of Al1-xScxN were studied. This work suggests that the origin of ferromagnetism of Al1-xScxN is the Al vacancies introduced by Sc ions. The amount of Al vacancies grew as the Sc doping ratio increased. According to the results of spin-polarized density of states (DOS), it is hypothesized that when the concentration of Al vacancies in Al1-xScxN grows, polarized itinerant electrons exist and result a magnetic phase change. (c) 2023 Elsevier B.V. All rights reserved.