Magnetron Sputter Epitaxy and Characterization of Wurtzite AlInN on Si(111) Substrates

AlInN films were grown on Si(111) substrates by the direct-current reactive sputtering method at temperatures from 150°C to 350°C. Growth of the AlInN films was found to be c-axis oriented, and the surfaces of the films were smooth. The bandgap structures and electron mobility of the AlInN films were studied using optical reflectance spectra and the Hall-effect method, respectively. The effects of an AlN buffer layer on the microstructure and optical and electrical properties of the AlInN films were investigated. It was found that the AlN buffer layer had a large influence on the crystalline quality and carrier concentration profiles of the AlInN films. This work suggests that reactive magnetron sputtering is a promising method for growing AlInN films at low temperatures.