The present work describes the growth and characterization of AIN thin films deposited by pulsed laser deposition (PLD), DC magnetron sputtering and filtered arc techniques. The focus of this paper is not only on the optimization of process parameters for the production of device quality thin AIN films, but also to investigate deposition techniques that could provide stable and reliable dielectric films wide band-gap power device. We investigated the working gas pressure dependence of the deposition of AIN on the vertical walls of the etched/patterned silicon for device passivation studies. Under high-pressure (13.334-93.343 Pa) conditions, high-density plasma was achieved which produced AIN passivation of a vertically etched Si wall. The films were characterized by X-ray diffraction (XRD), Rutherford backscattering and ion channeling spectrometry, atomic force microscopy (AFM), UV-visible spectroscopy, scanning electron microscopy (SEM).