Murata Manufacturing Co., Ltd.

Ken-ichi Uesaka

Tadashi Nomura

Masaki Takeuchi

Yukio Yoshino

Daisuke Nakamura

Hideki Kawamura

Hajime Yamada

Yoshimitsu Ushimi

Hiroyuki Fujino

Takashi Hayashi

Yoshihiko Gotoh

A piezoelectric thin film resonator having a stabilized temperature characteristic of resonant frequency, a method for manufacturing the same, and a communication apparatus using the piezoelectric thin film resonator are provided. The piezoelectric thin film resonator is provided with a substrate having an opening, first and second insulation films which are provided on one surface of the substrate while covering the opening and which primarily include SiOand AlO, respectively, AlOhaving oxygen defect and being in an amorphous state, and a piezoelectric thin film which is provided on the second insulation film and is sandwiched between electrodes and which primarily includes ZnO.

Method for manufacturing a piezoelectric resonator

A piezoelectric resonator includes a substrate and a vibrator. The vibrator includes a thin-film portion having at least one piezoelectric thin-film layer disposed on the substrate and at least one pair of upper and lower electrodes disposed on the substrate. The vibrator has a structure in which the thin-film portion is sandwiched from the upper and lower surfaces thereof by the upper and lower electrodes, which oppose each other in the depth direction, and the overlapping portion of the vibrator defined by the opposing upper and lower electrodes has a tetragonal shape, when viewed in the depth direction, other than a rectangle and a square, the tetragonal shape having substantially parallel sides having a longitudinal length equal to or smaller than about 10 times the oscillatory wavelength and also having at least one portion in which the distance between opposing electrode edges varies.

Piezoelectric resonator, and piezoelectric filter, duplexer, and communication apparatus, all including same

Piezoelectric resonator, piezoelectric filter, duplexer, communication apparatus, and method for manufacturing piezoelectric resonator

Growing community of inventors

Shiga-ken, Japan

Ken-ichi Uesaka