Voltage controlled oscillator

A voltage controlled oscillator comprising:

• a first thin film bulk acoustic wave resonator comprising;
• a first ferroelectric thin film equal to or smaller than 10 μm in thickness of perovskite type single crystal whose direction of polarization is aligned to the direction of thickness thereof;
• and
• a first and a second thin film electrodes provided interposing the first ferroelectric thin film between them:
• a second thin film bulk acoustic wave resonator comprising;
• a second ferroelectric thin film equal to or smaller than 10 μm in thickness of perovskite type single crystal whose direction of polarization is aligned to the direction of thickness thereof;
• and
• a third thin film electrode interposing the second ferroelectric thin film in cooperation with the second electrode, and
• deposited on the first thin film bulk acoustic wave resonator in the direction of thickness thereof and sharing the second electrode as a common electrode:
• a control voltage circuit applying a voltage between the electrodes:
• and
• an amplifier coupled with the first and the second thin film bulk acoustic wave resonators to constitute an oscillation circuit.

A voltage controlled oscillator comprising:

• a substrate:
• a first thin film bulk acoustic wave resonator provided on the substrate comprising;
• a ferroelectric thin film equal to or smaller than 10 μm in thickness of perovskite type single crystal whose direction of polarization is aligned to the direction of thickness thereof;
• and
• a first and a second thin film electrodes interposing the ferroelectric thin film between them:
• a second thin film bulk acoustic wave resonator comprising
• a third and a fourth thin film electrodes to interpose the ferroelectric thin film between them, provided adjacent to the first thin film bulk acoustic wave resonator on the substrate, and sharing the ferroelectric film with the first thin film bulk acoustic wave resonator:
• a control voltage circuit applying a voltage between the thin film electrodes:
• and
• an amplifier coupled with the first and the second thin film bulk acoustic wave resonators, constituting an oscillation circuit.

A voltage controlled oscillator comprising:

• a plurality of voltage controlled oscillators comprising;
• at least one thin film bulk acoustic wave resonator comprising;
• a ferroelectric thin film equal to or smaller than 10 μm in thickness of perovskite type single crystal whose direction of polarization is aligned to the direction of thickness thereof;
• and
• a pair of thin film electrodes interposing the ferroelectric thin film between them, and changing a resonant frequency by a voltage applied between the pair of thin film electrodes;
• a control voltage circuit applying the voltage between the pair of thin film electrodes;
• and
• an amplifier connected to the thin film bulk acoustic wave resonator to constitute an oscillation circuit in cooperation with the resonator:
• means for oscillating the plurality of the voltage controlled oscillators with different frequencies:
• and
• a multiplier connected to the plurality of the voltage controlled oscillators to output a difference of output frequencies of the voltage controlled oscillators.

A voltage controlled oscillator comprising:

• a substrate:
• a thin film bulk acoustic wave resonator provided on the substrate, comprising;
• a ferroelectric thin film equal to or smaller than 10 μm in thickness of perovskite type single crystal whose direction of polarization is aligned to the direction of thickness thereof;
• and
• a first and a second thin film electrodes provided so as to interpose the ferroelectric thin film between them:
• a switching element comprising thin film electrodes provided adjacent to the thin film bulk acoustic wave resonator on the substrate, and sharing the ferroelectric film with the thin film bulk acoustic wave resonator, so as to interpose the ferroelectric thin film between them, and applying the ferroelectric thin film as an actuator:
• a control voltage circuit applying a voltage between the first and the second electrodes:
• and
• an amplifier connected to the first and the second thin film bulk acoustic wave resonators so as to constitute an oscillation circuit.