Dielectric characteristics of a metal-insulator-metal (MIM) capacitor using plasma-enhanced chemical vapor deposited thin silicon nitride films have been evaluated. The capacitance values of the MIM capacitors are in proportion to the area of capacitors and in inverse proportion to the thickness of silicon nitride films. The breakdown strength of silicon nitride films with thicknesses of less than 0.2 mu m decreases because of the concentration of electrical fields at hillocks induced on the aluminum surface. However, about 3 MV/cm is obtained in the silicon nitride films with thicknesses of 0.1 mu m. The dielectric losses of the MIM capacitors are low enough up to the gigahertz regions.