Mitsubishi Denki Kabushiki Kaisha

Chisako Maeda

Akira Yamada

Fusaoki Uchikawa

Shusou Wadaka

Koichiro Misu

Toshio Umemura

Tsutomu Nagatsuka

Kenji Yoshida

Tomonori Kimura

Takahide Ishikawa

Takehiko Sato

Koji Ibata

Toshihisa Honda

Shunpei Kameyama

There is provided a film bulk acoustic wave device comprising: a silicon substrate , a dielectric film including a silicon nitride formed on the substrate and a silicon oxide on the silicon nitride , a bottom electrode formed on the dielectric film , a piezoelectric film formed on the bottom electrode , and a top electrode formed on the piezoelectric film , wherein a via hole is formed in such a manner that the thickness direction of a part of the silicon substrate which is opposite to a region including a part where the top electrode exists is removed from the bottom surface of the silicon substrate to a boundary surface with the silicon nitride

Film bulk acoustic wave device

A process for manufacturing a plurality of dielectric thin film devices by forming a lower layer on a substrate, coating a dielectric thin film on the lower layer, forming the dielectric thin film into a plurality of predetermined shapes, and, if desired, forming an upper structure on each of the plurality of dielectric thin films, wherein the dielectric thin film is divisionally formed on the lower layer by using a mask after the lower layer is formed to have a stress in a direction opposite to that of the dielectric thin film, or alternatively the dielectric thin film is divided into predetermined shapes after being formed.

Dielectric thin film element and process for manufacturing the same

A piezoelectric thin film device which is composed mainly of a substrate, a piezoelectric thin film formed on the substrate, and thin film electrodes formed on both the upper and lower surfaces of the thin film. The thin film is resonated by applying an AC voltage across the electrodes. A substrate removed section is formed by partially or entirely removing the substrate below the thin film and opened to both the front and rear surfaces of the substrate through openings so as to relieve the pressure variation in the substrate removed section below a resonant structure.

Piezoelectric thin film device

An electrode for a dielectric thin film device includes an adhesive layer adhering to a substrate, a diffusion suppressing layer containing compounds of metal elements constituting the adhesive layer or the substrate, and a main conduction layer. The crystallinity is enhanced by preventing diffusion of unnecessary elements into the dielectric thin film.

Electrode for dielectric-thin film device, and ultrasonic wave

Embodiments of the present invention provide a small and well-characterized bulk acoustic wave device by fabricating a filter having a wide band width or a resonator having a wide oscillation frequency range together with a semiconductor circuit. In embodiments of the present invention, a bulk acoustic wave device comprises a semiconductor substrate having a dielectric substance layer thereon, the dielectric substance layer has a ground conductor layer thereon, the ground conductor layer has a piezoelectric ceramic thin film thereon and the piezoelectric ceramic thin film has a conductive electrode pattern thereon. The thickness of the piezoelectric ceramic thin film is more than ten times the thickness of the ground conductor layer, and the wave number of acoustic waves that propagate in a direction parallel to a surface of the piezoelectric ceramic thin film multiplied by the thickness of the piezoelectric ceramic thin film is less than 2.

Growing community of inventors

Tokyo, Japan

Chisako Maeda