Optical and dielectric properties of dc magnetron sputtered AlN thin filmscorrelated with deposition conditions

Thin films of AlN were grown on glass and aluminium foil substrates by reac tive de magnetron sputtering. The films exhibit a columnar growth with surf ace roughness in the order of 8.8-5.2 nm. The optical and dielectric proper ties of the films were studied as a function of the nitrogen concentration in the reactive gas mixture. The refractive index and extinction coefficien t were found to be in the range of 1.93 to 2.3 and 10(-4)-10(-3) at lambda = 520 nm. The real part of dielectric constant and dielectric losses were m easured to be about 7.0 and 0.006-0.085, respectively, using metal-insulato r-metal (MIM) structures. (C) 1999 Published by Elsevier Science S.A. All r ights reserved.