Thin films are deposited on silicon substrates by the reaction of and N2 in an rf glow discharge at substrate temperatures between 25° and 500°C. These films are hereafter referred to as “nitrogen‐ films.” At optimum growth conditions an index of refraction of 2, a breakdown field strength of 107 V/cm, a flatband surface charge of , and a very high stability against bias temperature stress is obtained. With changing concentration the stoichiometry of the nitride films can be varied between highly nitrogen‐rich and silicon‐rich films resulting in a corresponding wide variation of physical and electrical film properties. Hysteresis‐free and highly stable varactors can be accomplished by an in situ glow discharge exposure in H2 and N2 atmosphere, respectively.