A resistance-capacitance oscillation circuit comprises an amplifier and a phase shifting circuit. The phase shifting circuit comprises at least three resistance-capacitance circuit elements, which comprise a resistance and a capacitance. At least one of the resistance-capacitance circuit elements comprises a variable resistance and a variable capacitance. The variable resistance is formed of a first electrode, a second electrode, a part of a semiconductor film, a part of a ferroelectric film, and a fourth electrode. The variable capacitor is formed of the second electrode, a third electrode, a fifth electrode, another part of the ferroelectric film, another part of the semiconductor film, and a paraelectric film.