Long-term exposure of a polycrystalline fullerene C_60 film in a constant electric field of 1–4 MV/cm produces an electroforming effect manifested by increase in conductivity of the film within several orders of magnitude. After this electroforming, the current–voltage ( I – U ) characteristic shows a high degree of current stability and reproducibility of results. In fields of 10^5–10^6 V/cm, the I – U characteristics of electroformed films are determined by the space-charge limited current. The concentration ( N _ t ≈ 4 × 10^21 m^–3) of carrier traps and their energy ( E _ t ≈ 0.176 eV) have been estimated.

In the frequency range from 30 Hz to 1 MHz, the dielectric properties of polycrystalline fullerite films with a thickness of about 300 nm, which are part of p-type Si / C60 / InGa structures, were studied under the influence of constant electric fields with a strength of up to 33 MV / m. It was found that at negative polarity of the InGa electrode, when the injection of electrons from the metal into the fullerite is facilitated, at frequencies less than 1000 Hz, an anomalous increase in the electrical capacity of the sample is observed, while the capacitance at a low frequency exceeds the capacitance at a high frequency by more than 1000 times. An explanation for this effect is proposed.