Abstract: A sensor chip is provided that includes a sensor element and a control circuit for controlling the sensor element disposed in semiconductor substrate. The control circuit includes a plurality of circuit elements, each of which is isolated by P-N junction separation. The sensor chip further includes a conductivity film disposed on and surrounding at least one of the circuit elements, and having an electric potential fixed to a predetermined value.

Abstract: A rotation detecting device is provided that detects the rotation of a rotating object by means of a biasing permanent magnet and multiple sensor chips. The sensor chips are disposed on front and back sides of a mounting chip along the rotation direction of the rotating object, aligned with a line perpendicular to the direction or rotation of the rotating object, so as to convert magnetic vectors of a magnetic field to a plurality of sensor signals. A selection circuit is connected to the magnetoresistance sensors and selects the one of the sensor signals whose magnitude is the largest.

Abstract: A current sensor includes: a current path; a semiconductor substrate; and a Hall element on the substrate. The Hall element detects a magnetic flux in a magnetic field caused by a detection object current. The Hall element generates a Hall voltage corresponding to the magnetic flux when a driving current flowing in a direction perpendicular to the semiconductor substrate is supplied to the Hall element, and when the magnetic flux having a component parallel to the semiconductor substrate affects the Hall element. The current path is disposed on the semiconductor substrate. The current path is electrically isolated from the Hall element.

Abstract: A current sensor includes: a current path; a semiconductor substrate; and a Hall element on the substrate. The Hall element detects a magnetic flux in a magnetic field caused by a detection object current. The Hall element generates a Hall voltage corresponding to the magnetic flux when a driving current flowing in a direction perpendicular to the semiconductor substrate is supplied to the Hall element, and when the magnetic flux having a component parallel to the semiconductor substrate affects the Hall element. The current path is disposed on the semiconductor substrate. The current path is electrically isolated from the Hall element.

Abstract: Rotation detecting apparatus for detecting rotation of a magnetic rotor includes: a sensor chip having a magnetoresistive device; and a bias magnet. The magnetoresistive device is capable of detecting change of a magnetic vector near the sensor chip so that the rotation detecting apparatus detects the rotation of the magnetic rotor. The change of the magnetic vector is generated by the bias magnetic field and the rotation of the magnetic rotor. The bias magnet is disposed around the sensor chip so that a deflection angle of the magnetic vector is controllable.

Abstract: A rotation detecting device detects rotation of a rotating object by means of a biasing permanent magnet and plural magnetoresistance sensors. The sensors are disposed along the rotation direction of the rotating object to convert magnetic vectors of a magnetic field to a plurality of sensor signals. A selection circuit is connected to the magnetoresistance sensors and selects one of the sensor signals whose magnitude is the largest.

Abstract: A semiconductor device includes: a semiconductor substrate including a first semiconductor layer, an insulation layer and a second semiconductor layer, which are laminated in this order; a trench penetrating both of the second semiconductor layer and the insulation layer and reaching the first semiconductor layer; and a third semiconductor layer. The trench has a ring shape on a principal surface of the substrate so that a part of the second semiconductor layer and a part of the insulation layer are surrounded with the trench. The third semiconductor layer is disposed in the trench through a first insulation film disposed on a sidewall of the trench so that the third semiconductor layer contacts the first semiconductor layer at a bottom of the trench.

Abstract: Rotation detecting apparatus for detecting rotation of a magnetic rotor includes: a sensor chip having a magnetoresistive device; and a bias magnet. The magnetoresistive device is capable of detecting change of a magnetic vector near the sensor chip so that the rotation detecting apparatus detects the rotation of the magnetic rotor. The change of the magnetic vector is generated by the bias magnetic field and the rotation of the magnetic rotor. The bias magnet is disposed around the sensor chip so that a deflection angle of the magnetic vector is controllable.

Abstract: A semiconductor sensor includes a P-type semiconductor substrate having a N-type semiconductor layer disposed on one surface of the substrate and a P-type diffused resistor disposed in the N-type semiconductor layer. A first electric voltage is applied to the N-type semiconductor layer, a second electric voltage is applied to the substrate, a third electric voltage is applied to the P-type diffused resistor. The first electric voltage is higher than the second and third electric voltages. The sensor ensures stable operation against electric leakage and high noise protection because two depletion layers are formed.

Abstract: A pressure sensor includes a sensor element, and a resin package member that holds the sensor element. The sensor element is constructed by a semiconductor, and is capable of externally outputting an electric signal in accordance with strain generated when force is applied thereto. The sensor element is directly adhered to the package member via an adhesive layer that has Young's modulus in a range between 2.45×103 Pa and 2.06×104 Pa. Further the adhesive layer has a thickness equal to or more than 110 ?m. Accordingly, the pressure sensor effectively restricts a variation in a sensor characteristic due to a thermal change.

Abstract: A semiconductor device includes: a semiconductor substrate including a first semiconductor layer, an insulation layer and a second semiconductor layer, which are laminated in this order; a trench penetrating both of the second semiconductor layer and the insulation layer and reaching the first semiconductor layer; and a third semiconductor layer. The trench has a ring shape on a principal surface of the substrate so that a part of the second semiconductor layer and a part of the insulation layer are surrounded with the trench. The third semiconductor layer is disposed in the trench through a first insulation film disposed on a sidewall of the trench so that the third semiconductor layer contacts the first semiconductor layer at a bottom of the trench.

Abstract: An external connection wire is externally connected and is bonded to a portion of a predetermined exposed region of a bonding pad, which is exposed through a bonding pad opening of a passivation film. The bonding pad opening of the passivation film has a polygonal shape that has a plurality of corners, and each of the plurality of corners has an obtuse angle or is chamfered. A probe pad is electrically connected to the bonding pad through a conductive line covered with the passivation film. The passivation film is also located on the probe pad and further includes a probe pad opening, through which a predetermined exposed region of the probe pad is exposed. The probe pad opening has a polygonal shape that has a plurality of corners, and each of the plurality of corners has an obtuse angle or is chamfered.

Abstract: In an integrated pressure sensor including a semiconductor substrate having a p type single crystal silicon substrate and an n type epitaxial layer of which a portion is etched by electrochemical etching to have a diaphragm, an impurity diffusion layer piercing the n type epitaxial layer at least defining the diaphragm is formed for isolation. An etching wire is formed on the surface of the n type epitaxial layer with insulation and the first end of the etching wire extends to the inside of the surface and connected to the n type epitaxial layer. The second opposite end extends to an edge of the semiconductor substrate. The etching wire does not cross the impurity layer inside the surface of the semiconductor substrate to prevent the etching wire from short-circuiting with the impurity diffusion layer during the electrochemical etching.

Abstract: First and second predetermined charging voltages are applied between the movable and fixed electrodes of a capacitive type of sensor to measure first and second capacitances between the movable and fixed electrodes, respectively. The first and second electrostatic capacitances are compared to obtain a characteristic of the sensor from a result of comparison. In measuring the first and second capacitances, first and second charging voltages are generated of which magnitudes are determined in accordance with the first and second capacitances, respectively. Equalization is made between the first output voltage when the first charging voltage is applied between the movable and fixed electrodes in a predetermined normal condition of the movable electrode and the second output voltage outputted when the second charging voltage is applied between the movable and fixed electrodes in the predetermined normal condition.

Abstract: A diaphragm-type semiconductor device includes a semiconductor substrate, a surface of which is substantially flat, a diaphragm, which covers a circular pressure reference space located on the surface, and a circular electrode layer, a middle part of which is embedded in the diaphragm. The electrode layer is larger than the space and is coaxial with the space. Therefore, internal stress is balanced between inner and outer sides of the diaphragm, and a step formed at the outer edge of the top electrode layer is separated from the diaphragm. The device also includes a step adjuster around the space on the surface. Therefore, another step formed at the outer edge of the space disappears, and a new step is formed separately from the diaphragm at the outer edge of the step adjuster. With this structure, the diaphragm has a desired flatness.

Abstract: A diaphragm-type semiconductor pressure sensor includes a substantially rectangular (110) semiconductor substrate, which has four sides, an active surface of (110) crystallographic face orientation, and a back surface, which is opposite to the active surface, of (110) crystallographic face orientation. Each of the surfaces is surrounded by the four sides. Each of the four sides is at an angle of substantially 45 degrees with a crystallographic axis of <110> orientation that is substantially parallel to the active surface. The substrate includes a diaphragm in the active surface. The diaphragm has been formed by forming a recess in the back surface. The diaphragm includes a gauge resistor. A pressure is detected on the basis of the variation in the resistance of the gauge resistor.

Abstract: In an integrated pressure sensor including a semiconductor substrate having a p type single crystal silicon substrate and an n type epitaxial layer of which a portion is etched by electrochemical etching to have a diaphragm, an impurity diffusion layer piercing the n type epitaxial layer at least defining the diaphragm is formed for isolation. An etching wire is formed on the surface of the n type epitaxial layer with insulation and the first end of the etching wire extends to the inside of the surface and connected to the n type epitaxial layer. The second opposite end extends to an edge of the semiconductor substrate. The etching wire does not cross the impurity layer inside the surface of the semiconductor substrate to prevent the etching wire from short-circuiting with the impurity diffusion layer during the electrochemical etching.

Abstract: In a capacitive sensor apparatus, a capacitive sensor includes a plurality of physical-quantity-detection capacitors each having a movable electrode and a fixed electrode. A conversion device operates for converting an output signal of the capacitive sensor into an apparatus output signal. Each of the physical-quantity-detection capacitors is selectively connected and disconnected to and from the conversion device. A determination is made as to whether or not each of the physical-quantity-detection capacitors fails in response to the sensor output signal. When it is determined that a first one of the physical-quantity-detection capacitors fails, the first one is disconnected from the conversion device and a second one of the physical-quantity-detection capacitors is connected to the conversion device.

Abstract: A dynamic sensor includes stationary electrodes and movable electrodes facing each other and forming a capacitance therebetween. The capacitance changes in accordance with a dynamic force such as acceleration imposed on the sensor. Plural projections are formed on the stationary electrodes to avoid or suppress electrode sticking between the movable electrodes and the stationary electrodes due to an excessive impact imposed on the sensor. The projections are formed to have various heights so that higher projections first hit the movable electrodes and thereby protect lower projections. Even after the higher projections are destroyed by the excessive impact, the lower projections remain intact and serve to prevent the electrode sticking by the excessive impact which may occur later.

Abstract: An external connection wire is externally connected and is bonded to a portion of a predetermined exposed region of a bonding pad, which is exposed through a bonding pad opening of a passivation film. The bonding pad opening of the passivation film has a polygonal shape that has a plurality of corners, and each of the plurality of corners has an obtuse angle or is chamfered. A probe pad is electrically connected to the bonding pad through a conductive line covered with the passivation film. The passivation film is also located on the probe pad and further includes a probe pad opening, through which a predetermined exposed region of the probe pad is exposed. The probe pad opening has a polygonal shape that has a plurality of corners, and each of the plurality of corners has an obtuse angle or is chamfered.