By means of reactive low voltage ion plating, AIN films were deposited onto unheated BK-7 glass, fused silica, and Si wafers. The obtained films were investigated mainly with respect to possible optical applications. Refractive index and absorption values were determined from spectrophotometric measurements. Hexagonal film structure, high density and smooth film surface and bulk film morphology were found by electron optical investigations. Mechanical characterization showed high hardness, good adherence to glass and compressive intrinsic film stress.