Semi‐insulating polycrystalline silicon (SIPOS) is a nonlinear, resistive film which is widely used as a passivant in high‐voltage planar electronic devices. We present current‐voltage and capacitance‐voltage data, taken from SIPOS capacitor structures, which are quite different from similar results in the literature. We propose that our data may be explained by the existence of a change in the current transport mechanism in the film at an anomalously low electric field value. We present an atomic resolution micrograph of the SIPOS/silicon interface which points to a possible morphological reason for the uniqueness of the current transport properties.