Electrical characteristics of insulating aluminum nitride MIS nanostructures

► We study the insulating properties of high-quality aluminum nitride thin films. ► The films exhibited (0 0 2) preferential orientation and were prepared as MIS. ► The dielectric constant has been found to depend on texture and thickness of films. ► Trapped charges at interface were estimated to be of the order of 1010 cm−2 eV−1.