Hitachi, Ltd.

Renesas Technology Corp.

Hitachi Automotive Systems, Ltd.

Hitachi Media Electronics Co., Ltd.

Chisaki Takubo

Atsushi Isobe

Noriyuki Sakuma

Yuudai Kamada

Takashi Shiota

Tomonori Sekiguchi

Tomonori Tanoue

Heewon Jeong

Mitsutaka Hikita

Kazuhiro Mochizuki

Isao Ohbu

Kenichi Tanaka

Hiroyuki Uchiyama

Takashi Oshima

Hidetoshi Matsumoto

Tatsuyuki Saito

Tatemi Ido

Kengo Asai

Nobuhiko Shibagaki

Kiyoko Yamanaka

Yuki Furubayashi

Kazuyuki Sakiyama

Provided are acceleration sensor, geophone and seismic prospecting system with high sensitivity and low power consumption. The acceleration sensor includes a mass body displaceable with respect to a rotation shaft. The acceleration sensor includes a first AC servo control facing a first symmetrical region of the first movable portion, a second AC servo control electrode facing a second symmetrical region of the second movable portion, and a DC servo control electrode facing an asymmetrical region of the second movable portion. A first AC servo capacitive element is formed by the first movable portion and the first AC servo control electrode, a second AC servo capacitive element is formed by the second movable portion and the second AC servo control electrode, and a DC servo capacitive element is formed by the second movable portion and the DC servo control electrode.

Acceleration sensor, geophone, and seismic prospecting system

Provided is an acceleration sensor having a large mass in a movable portion, and realizing high impact resistance. An acceleration sensor elementincludes an upper substrate, a lower substratespaced apart from the upper substrate, and an intermediate substrateprovided between the upper substrateand the lower substrate. Each of a first movable portion, a second movable portion, a frame portion, a fixed portion, and a spring portionconstituting the intermediate substrateis configured with two layers of an upper layer and a lower layer, and a stopper portionis provided at one end of the frame portion. A distancebetween an end portion of the first movable portionor the second movable portionand an end portion of the stopper portionin the upper layer and a distancebetween an end portion of the first movable portionor the second movable portionand an end portion of the stopper portionin the lower layer are different from each other.

Acceleration sensor

An acceleration sensor has high sensitivity, low power consumption and high linearity of output to the applied acceleration under gravity. To solve the above problem, the acceleration sensor is provided with a movable section placed between a base substrate and a cap substrate and rotating about a rotation axis. A top left electrode included in the cap substrate and a left movable electrode included in the movable section form a left capacitor, and a top right electrode included in the cap substrate and a right movable electrode included in the movable section form a right capacitor. Then, a lateral width of a first detection region in which capacitance is detected between the top left electrode and the left movable electrode, and a lateral width of a second detection region in which capacitance is detected between the top right electrode and the right movable electrode are different from each other.

In an acceleration sensor detecting a vibration acceleration by using torsion of a beam joining a fixed portion and a membrane, a spring constant of the beam is decreased while an increase in a chip size due to extension of the beam is prevented, so that an acceleration sensor that is highly sensitive and small in a size is provided with a low price. A sensor of a capacitance detecting type includes a membrane having a stacking structure formed of two or more layers and a plurality of beams capable of twisting so that the membrane is movable in a detecting direction, a first beam of the plurality of beams is formed of the same layer as either an upper or a lower layer of the membrane, and a second beam thereof is formed of the same layer as either an upper or a lower layer of the movable portion.

There is provided an acceleration sensor with low noise and high sensitivity. Specifically, a first number of opening portions are formed in a region corresponding to a heavyweight section of a mass body, on a surface of a membrane layer, and a second number of opening portions are formed in a region corresponding to the heavyweight section of the mass body, on a back surface of the membrane layer. The opening portion and the opening portion are connected to each other to form a plurality of through portions on the membrane layer, and the first number is larger than the second number.

An acceleration sensor with an improved membrane (mass body) is provided. The membrane includes a moving portion, a moving portion electrically separated from the moving portion, and a mechanical junction portion that mechanically connects the moving portion and the moving portion in a y-axis direction. The mechanical junction portion includes a first portion extending in a direction having a first angle with respect to the y-axis direction and a second portion extending in a direction having a second angle different from the first angle with respect to the y-axis direction in an xy plane, and is formed to have a non-linear shape in an x-axis direction. The acceleration sensor with improved the membrane stably operates by reducing a variation in a capacity value of a detection electrode and has an excellent noise characteristic.

Acceleration sensor including improved mass body

An acceleration sensor () includes a fixed portion (), a movable portion () connected to the fixed portion (), a lower electrode () that is disposed to face a lower surface of the movable portion (), and an upper electrode () that is disposed to face an upper surface of the movable portion (). A distance in an x-axis direction between an end portion () of the lower electrode () and the fixed portion () is shorter than a distance in the x-axis direction between an end portion () of the upper electrode () and the fixed portion (). Further, a distance in the x-axis direction between an end portion () of the lower electrode () and the fixed portion () is shorter than a distance in the x-axis direction between an end portion () of the upper electrode () and the fixed portion ().

There is provided an inertia sensor with low noise and high sensitivity. The inertia sensor captures a physical quantity as a change of electrostatic capacitance and detects the physical quantity based on a servo voltage generating electrostatic force that cancels the change of the electrostatic capacitance. The inertia sensor includes a detection capacitor unit that captures the physical quantity as the change of the electrostatic capacitance and a servo capacitor unit to which the servo voltage is applied. Here, the detection capacitor unit and the servo capacitor unit are connected mechanically through an insulation material.

Inertia sensor with improved detection sensitivity using servo voltage to detect a physical quantity

Airtightness in a cavity of an inertial sensor (acceleration sensor) is increased to achieve high sensitivity. In the acceleration sensor having movable electrodes VE, VEand fixed electrodes FE, FE, the fixed electrodes are formed by portions surrounded by a through hole THprovided in a cap layer CL, and the through hole is filled with an insulating film IFand polysilicon P and has a wide portion (WP). The wide portion has a gap SP that is not filled with the insulating film IFand the polysilicon P, and the gap SP is filled with the interlayer insulating film ID. With such a configuration, degassing can be exhausted through the gap (airway) SP in a pressure reducing step.

Inertia sensor and method of manufacturing the same

A semiconductor physical quantity detection sensor includes (1) a first electrostatic capacitance formed by the movable electrode, and a first fixed electrode formed in a first conductive layer shared with the movable electrode, (2) a second electrostatic capacitance that is formed by the movable electrode, and a second fixed electrode formed in a second conductive layer different in a height from a substrate surface from the movable electrode, and (3) an arithmetic circuit that calculates the physical quantity on the basis of a change in the first and second electrostatic capacitances generated when the physical quantity is applied. In this configuration, an electric signal from the first electrostatic capacitance, and an electric signal from the second electrostatic capacitance are input to the arithmetic circuit.

Semiconductor physical quantity detecting sensor

A protrusion formation hole is provided so as to pierce a support substrate. A polysilicon film as an electrical conducting material is embedded in the protrusion formation hole through an oxide silicon film. The polysilicon film partially bulges out of the protrusion formation hole toward a movable section to form a protruding section. In other words, the polysilicon film bulges out of the protrusion formation hole toward the movable section to form the protruding section. Thereby, a movable section included in MEMS can be prevented from sticking to other members.

MEMS device and method of manufacturing MEMS device

The present invention provides a semiconductor device which comprises active components, passive components, wiring lines and electrodes and are satisfactory in terms of mechanical strength, miniaturization and thermal stability. In the semiconductor device, openings are formed just below active components. These openings are filled with conductor layers. Conductor layers are also formed where openings are not formed.

Semiconductor HBT MMIC device and semiconductor module

The gist of the present invention is as follows: In a monolithic microwave integrate circuit (MMIC) using a heterojunction bipolar transistor (HBT), via holes are respectively formed from the bottom of the MMIC for the emitter, base and collector. Of the via holes, one is located so as to face the HBT. The respective topside electrodes for the other via holes located so as not to face the HBT are provided in contact with the MMIC substrate.

Semiconductor device having led out conductor layers, manufacturing method of the same, and semiconductor module

A surface acoustic wave signal processing apparatus for processing first and second high-frequency signals having frequencies f.sub.1 and f.sub.2 respectively, which comprises: first and second surface acoustic wave delay elements for receiving the first and second high-frequency signals respectively and independently of each other, the delay elements being formed as surface acoustic wave excitation and reception transducers on a piezoelectric substrate so that a phase delay .phi..sub.1 with respect to the frequency f.sub.1 is substantially equal to a phase delay .phi..sub.2 with respect to the frequency f.sub.2 (that is, .phi..sub.1 .apprxeq..phi..sub.2); and a mixer for mixing first and second high-frequency output signals of the first and second surface acoustic wave delay elements so that a signal having a frequency .vertline.f.sub.1 -f.sub.2 .vertline. which is a difference between the two frequencies f.sub.1 and f.sub.2 is taken out as an output signal of the mixer.

CDMA communication RF signal processing apparatus using SAW

Aluminum is used for the interdigital transducer mounted on a piezoelectric substrate to realize a surface acoustic wave transducer having a small capacity ratio, no spurious resonance, and a low loss. A .theta. rotated Y cut lithium niobate single crystal piezoelectric substrate is used for the piezoelectric material, a metal film of which principal ingredient is aluminum is used for the interdigital transducer, the direction of the interdigital transducer is made parallel to the X-axis of the lithium niobate single crystal, and thick h and electrode pitch P of the interdigital transducer have the following relationship:

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Tokyo, Japan

Chisaki Takubo