Abstract: A vehicle steering system includes a clutch provided on a power transmission path extending from a steering wheel to steered wheels, a reactive-force motor connected to a first portion of the power transmission path, which is closer to the steering wheel than the clutch is, a steering motor including a first motor coil and a second motor coil, and connected to a second portion of the power transmission path, which is closer to the steered wheels than the clutch is, a driving circuit configured to supply electric power to the reactive-force motor, a first driving circuit configured to supply electric power to the first motor coil, and a second driving circuit configured to supply electric power to the second motor coil.

Abstract: The present invention provides a method of manufacturing a solar cell, comprising forming a buffer layer comprising a group-III nitride semiconductor on a substrate using a sputtering method, and forming a group-III nitride semiconductor layer and electrodes on the buffer layer. The group-III nitride semiconductor layer is formed on the buffer layer by at least one selected from the group consisting of the sputtering method, a MOCVD method, an MBE method, a CBE method, and an MLE method, and the electrodes are formed on the group-III nitride semiconductor layer.

Abstract: There are provided a group III nitride semiconductor light emitting device which is constituted of a substrate, an intermediate layer formed thereon having a favorable level of orientation properties, and a group III nitride semiconductor formed thereon having a favorable level of crystallinity, and having excellent levels of light emitting properties and productivity; a production method thereof; and a lamp, the group III nitride semiconductor light emitting device configured so that at least an intermediate layer 12 composed of a group III nitride compound is laminated on a substrate 11, and an n-type semiconductor layer 14 having a base layer 14a, a light emitting layer 15 and a p-type semiconductor layer 16 are sequentially laminated on the intermediate layer 12, wherein when components are separated, based on a peak separation technique using an X-ray rocking curve of the intermediate layer 12, into a broad component having the full width at half maximum of 720 arcsec or more and a narrow component,

Abstract: An object of the present invention is to obtain a group III nitride compound semiconductor stacked structure where a group III nitride compound semiconductor layer having good crystallinity is stably stacked on a dissimilar substrate. The group III nitride compound semiconductor stacked structure of the present invention is a group III nitride compound semiconductor stacked structure comprising a substrate having provided thereon a first layer comprising a group III nitride compound semiconductor and a second layer being in contact with the first layer and comprising a group III nitride compound semiconductor, wherein the first layer contains a columnar crystal with a definite crystal interface and the columnar crystal density is from 1×103 to 1×105 crystals/?m2.

Abstract: A manufacturing method of a semiconductor element formed by multi-layering on a substrate so as to include an n-type semiconductor and a p-type semiconductor. The method includes a process of sputtering, with a gas including a group V element, at least two targets (a first target 21 and a second target 22) made of group III elements that are different from each other, thereby to form a film of a III-V compound semiconductor on the substrate 110.

Abstract: There are provided a group III nitride semiconductor light emitting device which is constituted of a substrate, an intermediate layer formed thereon having a favorable level of orientation properties, and a group III nitride semiconductor formed thereon having a favorable level of crystallinity, and having excellent levels of light emitting properties and productivity; a production method thereof; and a lamp, the group III nitride semiconductor light emitting device configured so that at least an intermediate layer 12 composed of a group III nitride compound is laminated on a substrate 11, and an n-type semiconductor layer 14 having a base layer 14a, a light emitting layer 15 and a p-type semiconductor layer 16 are sequentially laminated on the intermediate layer 12, wherein when components are separated, based on a peak separation technique using an X-ray rocking curve of the intermediate layer 12, into a broad component having the full width at half maximum of 720 arcsec or more and a narrow component,

Abstract: The present invention provides a method of manufacturing a solar cell, comprising forming a buffer layer comprising a group-III nitride semiconductor on a substrate using a sputtering method, and forming a group-III nitride semiconductor layer and electrodes on the buffer layer. The group-III nitride semiconductor layer is formed on the buffer layer by at least one selected from the group consisting of the sputtering method, a MOCVD method, an MBE method, a CBE method, and an MLE method, and the electrodes are formed on the group-III nitride semiconductor layer.

Abstract: The object of the present invention is to provide a solar cell which is industrially beneficial and has high light conversion efficiency; and a method for producing a solar cell; and the present invention provides a solar cell comprising a substrate, a power generation layer for converting received light into electrical power, a translucent electrode, and another electrode, when light travels through each member from a first surface thereof, a surface opposite to the first surface is defined as a second surface, the power generation layer is formed at a second surface side of the substrate, the translucent electrode is formed on one surface of the power generation layer, and another electrode is formed on the other surface of the power generation layer, wherein the translucent electrode comprises hexagonal In2O3 crystal.

Abstract: A group-III nitride compound semiconductor device of the present invention comprises a substrate, an intermediate layer provided on the substrate, and a base layer provided on the intermediate layer in which a full width at half maximum in rocking curve of a (0002) plane is 100 arcsec or lower and a full width at half maximum in rocking curve of a (10-10) plane is 300 arcsec or lower. Also, a production method of a group-III nitride compound semiconductor device of the present invention comprises forming the intermediate layer by using a sputtering method.

Abstract: An object of the present invention is to obtain a group III nitride compound semiconductor stacked structure where a group III nitride compound semiconductor layer having good crystallinity is stably stacked on a dissimilar substrate. The group III nitride compound semiconductor stacked structure of the present invention is a group III nitride compound semiconductor stacked structure comprising a substrate having provided thereon a first layer comprising a group III nitride compound semiconductor and a second layer being in contact with the first layer and comprising a group III nitride compound semiconductor, wherein the first layer contains a columnar crystal with a definite crystal interface and the columnar crystal density is from 1×103 to 1×105 crystals/?m2.

Abstract: The present invention provides a solar cell that is useful for industry and has high photoelectric conversion efficiency and a method of manufacturing the same. A solar cell according to an aspect of the invention includes: a substrate; a buffer layer that is formed on the substrate and is composed of a group-III nitride semiconductor; and a group-III nitride semiconductor layer (p-type layer/an n-type layer) that has a p-n junction therein and is formed on the buffer layer. At least one of the buffer layer and the group-III nitride semiconductor layer having the p-n junction therein has a compound semiconductor layer formed by a sputtering method.

Abstract: An electric power steering system is provided which assists a steering operation by applying a driving force generated by an electric motor to a steering mechanism of a motor vehicle. The system includes a sensor (e.g., a torque sensor) for acquiring information necessary for controlling the electric motor, and a board provided adjacent the electric motor and having a sensor signal processing circuit for processing a signal from the sensor. A temperature sensor for acquiring temperature information necessary for controlling the electric motor is mounted on the board.

Abstract: An electric power steering system is provided, which employs an electric motor as a drive source to apply a steering assist force to a steering mechanism mounted on a motor vehicle in accordance with the operation of an operation member. The electric power steering system includes: a torque sensor which detects a steering torque applied to the operation member and outputs a torque signal in accordance with the detected steering torque; and a motor driving control circuit which outputs a motor driving command signal for driving the electric motor on the basis of the torque signal outputted from the torque sensor. At start or stop of the operation of the electric power steering system, the motor driving command signal is limited in accordance with the magnitude of the steering torque detected by the torque sensor.

Abstract: A motor is stopped when a steering angular speed is not greater than a stop threshold VS and a motor electric current value Im is kept within a motor stop range &Dgr;I for a predetermined time period. The value of a steering torque increases as the motor electric current value Im increases. Therefore, the motor can assuredly be stopped when the steering torque is small. Further, when the motor is off, the sensitivity for motor actuation with respect to a change in the steering angle is set higher as the value of the steering angle increases.

Abstract: An electric power steering system is provided which assists a steering operation by applying a driving force generated by an electric motor to a steering mechanism of a motor vehicle. The system includes a sensor (e.g., a torque sensor) for acquiring information necessary for controlling the electric motor, and a board provided adjacent the electric motor and having a sensor signal processing circuit for processing a signal from the sensor. A temperature sensor for acquiring temperature information necessary for controlling the electric motor is mounted on the board.

Abstract: A power steering apparatus which generates a steering assist force to be applied to a steering mechanism by a hydraulic pressure generated by a pump driven by an electric motor. The apparatus determines a rotation speed of the motor in accordance with a steering angular speed sensed when the steering mechanism is operated. The motor is driven at a lower motor rotation speed when the steering mechanism is operated toward a steering angle midpoint than when the steering mechanism is operated away from the steering angle midpoint.

Abstract: This invention provides a power steering apparatus for assisting steering by utilizing a hydraulic pump to be driven by an electric motor as a generating source of a hydraulic pressure. A drive voltage determination unit determines a drive voltage so that a rotational velocity of the electric motor detected by a rotational velocity sensor and a rotational velocity detecting circuit becomes a first rotational velocity on the occasion of starting of the electric motor, and determines a gradually increasing drive voltage after the electric motor is started by the determined drive voltage until the detected rotational velocity reaches the second rotational velocity. Therefore, an unnecessary inrush current is not generated in the electric motor, and the rotational velocity of the electric motor does not overshoot.

Abstract: A power steering apparatus which generates a steering assist force by a hydraulic pressure generated by a pump driven by an electric motor. The power steering apparatus actuates the electric motor in its off state, on condition that a change amount of a steering angle exceeds an actuation threshold. A first actuation threshold which is to be employed when a steering wheel is operated away from a steering angle midpoint and a second actuation threshold which is to be employed when the steering wheel is operated toward the steering angle midpoint are determined in accordance with a sensed steering angle so that the sum of the first and second actuation thresholds is virtually constant.

Abstract: In a power steering apparatus according to the present invention, a threshold ITH of a motor electric current for actuation of an oil pump is set at a lower level when a working oil has a high viscosity resistance at a low oil temperature, so that the oil pump can be actuated at an earlier stage. Conversely, when the working oil has a low viscosity resistance at a high oil temperature, the threshold ITH of the motor electric current for the actuation of the oil pump is set at a higher level because there is no need to actuate the oil pump at the earlier stage. Thus, the electric motor can be actuated without any problem even at an extremely low temperature, so that an entrapped feeling can promptly be mitigated.

Abstract: A motor is stopped (S14), if a steering angular speed V.theta. which is the time-related change rate of a steering angle is not greater than a stop threshold value Vb (YES in S10) and a motor electric current value Im is kept within a motor stop range .DELTA.I predetermined on the basis of a non-load electric current value for a predetermined time period (YES in S12, S13). The non-load electric current value is an electric current value observed at a steering torque of zero and, therefore, the motor stop range corresponds to a range where no steering assist force is required. That is, when the steering angular speed V.theta. and the steering torque are small, the steering assist is regarded unnecessary, and the motor is stopped.