Murata Manufacturing Co., Ltd.

Akira Konno

Masakazu Mimura

Ville-Pekka Rytkönen

Yoshitaka Kato

The present invention relates to capacitive micromechanical accelerometers, and in particular to acceleration sensors with movable rotors which may rotate out of a substrate plane when the accelerometer undergoes movement with an acceleration component perpendicular to the substrate plane. The capacitive micromechanical accelerometer includes additional damping springs to reduce unwanted movement of the rotor in the substrate plane, thereby reducing the parasitic capacitance that results from motion of the rotor in the substrate plane. The damping springs are vertically recessed with respect to other components of the accelerometer in order to minimise the effect of the damping springs on movement of the rotor out of the substrate plane.

Capacitive micromechanical accelerometer

An elastic wave device includes an IDT electrode and an insulating film on a piezoelectric substrate. Above an intersection region of the IDT electrode, when one end in an elastic-wave propagation direction is a first end portion and the other end in the elastic-wave propagation direction is a second end portion, the thickness of the insulating film is decreased or increased towards a center in the elastic-wave propagation direction from the first end portion and the second end portion.

Elastic wave device

An elastic wave device includes a LiNbOsubstrate, an IDT electrode provided on the LiNbOsubstrate, and a dielectric film that is provided on the LiNbOsubstrate so as to cover the IDT electrode and includes a projection on an upper surface of the stated dielectric film. A main mode of an elastic wave excited by the IDT electrode uses a Rayleigh wave, and a thickness of the IDT electrode is set such that a frequency at which a response by an SH wave appears is lower than a resonant frequency of the Rayleigh wave.

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Nagaokakyo, Japan

Akira Konno