Abstract: A pressure sensor according to an aspect of the present invention comprises a plurality of piezoelectric elements that are sheet-like and laminated, wherein: the plurality of piezoelectric elements are divided into a plurality of element groups; and the plurality of element groups are connected in parallel and in each element group the piezoelectric elements are connected in series, or the plurality of element groups are connected in series and in each element group the piezoelectric elements are connected in parallel.

Abstract: An electronic blood pressure monitor includes: a vibration sensor that includes a film shape, the vibration sensor detecting vibrations of a body surface, the vibration sensor converting the detected vibrations to an electrical signal corresponding to pressure generated in a thickness direction of the vibration sensor to output the electrical signal; and a stethoscope filter that passes a signal of a first predetermined frequency band among the output electrical signal, the first predetermined frequency band being determined based on a frequency characteristic of a stethoscope.

Abstract: A pressure sensor according to an aspect of the present invention comprises a plurality of piezoelectric elements that are sheet-like and laminated, wherein: the plurality of piezoelectric elements are divided into a plurality of element groups; and the plurality of element groups are connected in parallel and in each element group the piezoelectric elements are connected in series, or the plurality of element groups are connected in series and in each element group the piezoelectric elements are connected in parallel.

Abstract: An ultrasonic inspection device includes a signal generator configured to generate a square wave burst signal, an ultrasonic wave transmitter configured to drive a probe according to the square wave burst signal output from the signal generator and transmit ultrasonic waves toward an inspection subject, an ultrasonic wave receiver configured to receive the ultrasonic waves transmitted toward the inspection subject and propagated through the inspection subject, and a defect determinator configured to determine the presence or absence of a defect in the inspection subject based on a signal from the ultrasonic wave receiver, wherein the square wave burst signal has square waves that continuously alternate due to positive voltages and negative voltages relative to a ground.

Abstract: A condenser microphone includes a substrate having a cavity, first and second spacers defining an opening, a diaphragm having a rectangular shape positioned inside of the opening, and a plate having a rectangular shape positioned just above the diaphragm. Plate joint portions integrally interconnected with two sides of the plate are directly attached onto the second spacer. Supports, which are attached onto the second spacer across the opening and project inwardly of the opening, are connected to the prescribed portions of the diaphragm via third spacers relatively to the other two sides of the plate. The center portion of the diaphragm can be designed in a multilayered structure, and the peripheral portion can be bent outwardly. In addition, both ends of the diaphragm are fixed in position, while free ends of the diaphragm vibrate due to sound waves.

Abstract: A plurality of structures of condenser microphones is fabricated in a single condenser microphone array chip. The condenser microphone array chip includes a substrate having a plurality of openings serving as air cavities, a first insulating layer formed in the outer periphery of the openings, a first electrode layer stretched over each of the openings, a second insulating layer formed above the first electrode layer in the outer periphery of the openings, a second electrode layer formed above the second insulating layer relative to the first electrode layer via an air gap therebetween. The structures are connected via a plurality of bridges and separated via a plurality of channels therebetween. The channels circumvent the bridges so that at least the second insulating layer is partially removed from the channels. The bridges are formed using the second electrode layer serving as wiring for electrically connecting the structures of condenser microphones.

Abstract: A plurality of structures of condenser microphones is fabricated in a single condenser microphone array chip. The condenser microphone array chip includes a substrate having a plurality of openings serving as air cavities, a first insulating layer formed in the outer periphery of the openings, a first electrode layer stretched over each of the openings, a second insulating layer formed above the first electrode layer in the outer periphery of the openings, a second electrode layer formed above the second insulating layer relative to the first electrode layer via an air gap therebetween. The structures are connected via a plurality of bridges and separated via a plurality of channels therebetween. The channels circumvent the bridges so that at least the second insulating layer is partially removed from the channels. The bridges are formed using the second electrode layer serving as wiring for electrically connecting the structures of condenser microphones.

Abstract: The present invention provides a condenser microphone, in which, with a simple manufacturing process, vibration characteristics of a diaphragm are improved, and a parasitic capacitance occurring between the diaphragm and a back plate is reduced, thus improving sensitivity. Specifically, the diaphragm having a gear-like shape including a center portion and a plurality of arms and the back plate having a gear-like shape including a center portion and a plurality of arms are positioned opposite to each other above a substrate, wherein the arms of the diaphragm and the arms of the back plate are not positioned opposite to each other. Alternatively, it is possible to independently support the diaphragm and the back plate above the substrate. Furthermore, it is possible to support the back plate above the substrate by means of a plurality of supports inserted into a plurality of holes formed in the center portion of the diaphragm.

Abstract: A capacitor microphone is constituted by a plate having a fixed electrode, a diaphragm including a center portion and at least one near-end portion that is fixed to the outer periphery, in which the center portion having a vibrating electrode, which is positioned relative to the fixed electrode and which vibrates in response to sound waves, is increased in rigidity in comparison with the near-end portion; and a spacer that is fixed to the plate and the near-end portion of the diaphragm and that has an air gap formed between the plate and the diaphragm. Alternatively, a diaphragm electrode is horizontally supported by extension arms extended from a circular plate thereof and is vertically held in a hanging state being apart from a fixed electrode with a controlled distance therebetween.

Abstract: An MEMS transducer is constituted of a diaphragm, a plate, a support structure for supporting the diaphragm and the plate with a gap layer surrounded by an interior wall, an electrode film (e.g. a pad conductive film) for covering a contact hole formed in the support structure, and a protective film (e.g. a pad protective film) which is formed on the support structure externally of the interior wall so as to cover the side surface of the electrode film having low chemical stability. The protective film is formed in the limited area including a part of the surface of the electrode film except for its center portion and the surrounding area of the electrode film. This allows the protective film to use materials having high membrane stress such as silicon nitride or silicon nitride oxide.

Abstract: A semiconductor device is equipped with a semiconductor sensor chip for detecting pressure variations that is arranged inside of a hollow cavity of a housing, wherein an opening is formed in a prescribed region of the housing, which is not positioned opposite to the semiconductor sensor chip, so as to allow the hollow cavity to communicate with an external space. The opening is formed using at least one through-hole having a thin slit-like shape. Alternatively, the opening is formed using plural through-holes each having a desired shape such as a thin slit-like shape, a circular shape, and a sectorial shape. Thus, it is possible to reduce negative influences due to environmental factors such as dust and sunlight with respect to the semiconductor sensor chip.

Abstract: An MEMS transducer is constituted of a diaphragm, a plate, a support structure for supporting the diaphragm and the plate with a gap layer surrounded by an interior wall, an electrode film (e.g. a pad conductive film) for covering a contact hole formed in the support structure, and a protective film (e.g. a pad protective film) which is formed on the support structure externally of the interior wall so as to cover the side surface of the electrode film having low chemical stability. The protective film is formed in the limited area including a part of the surface of the electrode film except for its center portion and the surrounding area of the electrode film. This allows the protective film to use materials having high membrane stress such as silicon nitride or silicon nitride oxide.

Abstract: A vibration transducer includes a substrate, a diaphragm formed using deposited films having conductive property, which has a plurality of arms extended from the center portion in a radial direction, a plate formed using deposited films having conductive property, and a plurality of diaphragm supports formed using deposited films, which join the arms so as to support the diaphragm above the substrate with a prescribed gap therebetween. A plurality of bumps is formed in the arms of the diaphragm so as to prevent the diaphragm from being attached to the substrate or the plate. When the diaphragm vibrates relative to the plate, an electrostatic capacitance therebetween is varied so as to detect variations of pressure applied thereto. In addition, a plurality of diaphragm holes is appropriately aligned in the arms of the diaphragm so as to improve the sensitivity while avoiding the occurrence of adherence.

Abstract: A vibration transducer (e.g. a condenser microphone) having a high sensitivity is constituted of a housing composed of an airtight material having a through-hole, a vibration conversion die (e.g. a microphone die) which is attached to the interior surface of the housing at the prescribed position embracing the through-hole in plan view, and a barrier diaphragm composed of an airtight material whose external periphery is attached to the exterior surface of the housing in an airtight manner oppositely to the prescribed position. The barrier diaphragm has a vibration area which is larger than the sectional area of the through-hole. A space allowing the barrier diaphragm to vibrate is formed between the barrier diaphragm and the exterior surface of the housing, wherein the distance between the barrier diaphragm and the exterior surface of the housing can be gradually reduced from the vibration axis to the external periphery.

Abstract: A vibration transducer is constituted of a substrate, a diaphragm having a conductive property, a plate having a conductive property, and a plurality of first spacers having pillar shapes which are formed using a deposited film having an insulating property joining the plate so as to support the plate relative to the diaphragm with a gap therebetween. It is possible to introduce a plurality of second spacers having pillar shapes support the plate relative to the substrate with a gap therebetween, and/or a plurality of third spacers having pillar shapes which support the diaphragm relative to the substrate with a gap therebetween. When the diaphragm vibrates relative to the plate, an electrostatic capacitance formed therebetween is varied so as to detect vibration with a high sensitivity. The diaphragm has a plurality of arms whose outlines are curved so that the intermediate regions thereof are reduced in width.

Abstract: A semiconductor device is equipped with a semiconductor sensor chip for detecting pressure variations that is arranged inside of a hollow cavity of a housing, wherein an opening is formed in a prescribed region of the housing, which is not positioned opposite to the semiconductor sensor chip, so as to allow the hollow cavity to communicate with an external space. The opening is formed using at least one through-hole having a thin slit-like shape. Alternatively, the opening is formed using plural through-holes each having a desired shape such as a thin slit-like shape, a circular shape, and a sectorial shape. Thus, it is possible to reduce negative influences due to environmental factors such as dust and sunlight with respect to the semiconductor sensor chip.

Abstract: An electrostatic pressure transducer (e.g., a condenser microphone) includes a plate having a plurality of holes and forming a fixed electrode, a diaphragm forming a vibrating electrode, at lease one spacer that is positioned between the plate and the diaphragm in the ring-shaped internal area internally of the peripheral end of the diaphragm, and a stopper plate having an opening, which is positioned opposite to the plate with respect to the diaphragm. The diaphragm vibrates relative to the plate in such a way that, due to electrostatic attraction, the internal portion thereof moves close to the plate while the external portion thereof moves opposite to the plate, wherein the peripheral end thereof partially comes in contact with the opening edge of the stopper plate. Thus, it is possible to realize flat frequency characteristics while improving the sensitivity in low-frequency ranges.

Abstract: In a silicon microphone, a corrugation is formed in a conductive layer between a center portion forming a diaphragm and a periphery, wherein the corrugation is formed on an imaginary line connecting a plurality of supports formed in a circumferential direction of the conductive layer, whereby it is possible to increase the rigidity of the conductive layer; hence, distortion or deformation may hardly occur in the conductive layer irrespective of variations of stress applied thereto. Alternatively, a planar portion is continuously formed on both sides of a step portion in the plate so as to increase its rigidity, wherein a plurality of holes are uniformly formed and arranged in the planar portion by avoiding the step portion. Thus, it is possible to realize a high sensitivity and uniformity of performance and characteristics in the silicon microphone.

Abstract: The present invention provides a condenser microphone, in which, with a simple manufacturing process, vibration characteristics of a diaphragm are improved, and a parasitic capacitance occurring between the diaphragm and a back plate is reduced, thus improving sensitivity. Specifically, the diaphragm having a gear-like shape including a center portion and a plurality of arms and the back plate having a gear-like shape including a center portion and a plurality of arms are positioned opposite to each other above a substrate, wherein the arms of the diaphragm and the arms of the back plate are not positioned opposite to each other. Alternatively, it is possible to independently support the diaphragm and the back plate above the substrate. Furthermore, it is possible to support the back plate above the substrate by means of a plurality of supports inserted into a plurality of holes formed in the center portion of the diaphragm.

Abstract: A condenser microphone includes a substrate having a cavity, first and second spacers defining an opening, a diaphragm having a rectangular shape positioned inside of the opening, and a plate having a rectangular shape positioned just above the diaphragm. Plate joint portions integrally interconnected with two sides of the plate are directly attached onto the second spacer. Supports, which are attached onto the second spacer across the opening and project inwardly of the opening, are connected to the prescribed portions of the diaphragm via third spacers relatively to the other two sides of the plate. The center portion of the diaphragm can be designed in a multilayered structure, and the peripheral portion can be bent outwardly. In addition, both ends of the diaphragm are fixed in position, while free ends of the diaphragm vibrate due to sound waves.