Murata Manufacturing Co., Ltd.

Sachihito Nakafuku

Kiyoshi Iyama

Mikio Nakashima

A piezoelectric electroacoustic transducer, including a plurality of piezoelectric layers deposited to define a deposited product, flexurally vibrates the deposited product by polarizing the entire piezoelectric ceramic layers in the same thickness direction and also by applying an alternating signal between external electrodes disposed on the front/rear major surfaces of the deposited product and an internal electrode disposed between the ceramic layers. A dummy electrode is provided between the ceramic layers outside the internal electrode via a gap, and a portion of the internal electrode is exposed at at least one side surface of the piezoelectric ceramic layers, while the dummy electrode is exposed at the other side surface of the piezoelectric ceramic layers. The external electrodes extend to the side surfaces other than the side surface at which the internal electrode is exposed.

Piezoelectric electroacoustic transducer and manufacturing method of the same

A method for adjusting the frequency of a piezoelectric resonator allows for frequency adjustments to be individually made for each of a plurality of elements disposed on a piezoelectric substrate before the resonator is completed. Moreover, the frequency adjustments can be made with high accuracy in a relatively short time. When adjusting the frequency of each element, an ion beam is irradiated onto a plurality of electrodes disposed on the piezoelectric substrate to etch the electrodes. The method includes the steps of determining a correlation between an ion-beam irradiation time and the amount of frequency changes, measuring the frequency of each element on the piezoelectric substrate, determining the amount of the frequency adjustment of the element based on a difference between the measured frequency and a target value, determining the ion-beam irradiation time for the element based on the determined amount of the frequency adjustment by using the correlation, and irradiating an ion beam onto the element during the determined irradiation time.

Method for adjusting frequency of piezoelectric resonator

A method of adjusting a frequency of an energy-trap type piezoelectric resonance element includes the steps of preparing a piezoelectric resonance element including first and second vibration electrodes formed partially on both of the main surfaces of a piezoelectric plate, the thickness of the first vibration electrode being larger than that of the second vibration electrode, and modifying the first vibration electrode or the second vibration electrode in such a manner that the thicknesses of the first and second vibration electrode electrodes are substantially equal to each other such that the piezoelectric resonance element has a desired frequency.

Method of adjusting frequency of piezoelectric resonance element by removing material from a thicker electrode or adding, material to a thinner electrode

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Toyama, Japan

Sachihito Nakafuku