Abstract: A single crystal semiconductor manufacturing method for realizing a dislocation-free single crystal while not varying or hardly varying electric power supplied to a heater when and after a seed crystal comes into contact with a melt. The allowable temperature difference ?Tc not causing dislocation in the seed crystal is determined according to the concentration (C) of the impurities added to the seed crystal (14) and the size (diameter D) of the seed crystal (14). When the seed crystal (14) comes into contact with the melt (5), electric power supplied to a bottom heater (19) is fixed, and a magnetic field produced by a magnet (20) is applied to the melt (5). Electric power supplied to a main heater (9) is controlled so that the temperature at the surface of the melt (5) which the seed crystal (14) comes into contact with may be a target value. After the seed crystal (14) comes into contact with the melt (5), single crystal silicon is pulled up without performing a necking process.

Abstract: A control device for a gas sensor is configured to: receive a mode command to specify one of a plurality of sensor energization modes including at least a gas concentration detection mode, a protection mode and a pre-energization mode; switch a sensor element of the gas sensor into the one of the plurality of sensor energization modes according to the mode command; judge satisfaction of a certain condition where the mode command is to specify the gas concentration detection mode and the sensor element is in any of the plurality of sensor energization modes other than the pre-energization mode at the time of receipt of the mode command; and prohibit the sensor element from switching over to the gas concentration detection mode when the certain condition is satisfied.

Abstract: The present invention is to produce a silicon crystal wherein the boron concentration in the silicon crystal and the growth condition V/G are controlled so that the boron concentration in the silicon crystal is no less than 1×1018 atoms/cm3 and the growth condition V/G falls within the epitaxial defect-free region ?2 whose lower limit line LN1 is the line indicating that the growth rate V gradually drops as the boron concentration increases. A silicon wafer is also produced wherein the boron concentration in the silicon crystal and the growth condition V/G are controlled so as to include at least the epitaxial defect region ?1, and both the heat treatment condition and the oxygen concentration of the silicon crystal are controlled so that no OSF nuclei grow to OSFs.

Abstract: An interface device for a gas sensor includes a detection resistor having first and second ends to generate voltages by a current output of the gas sensor, a differential amplifier having first and second input terminals to receive the voltages of the first and second resistor ends and an output terminal to output a voltage according to a difference between the voltages of the first and second resistor ends, a first switching element to transmit the voltage of the first resistor end to the first input terminal of the differential amplifier in a transmission state and interrupt transmission of the voltage of the first resistor end to the first input terminal of the differential amplifier in an interruption state and a second switching element turned on to establish continuity between the first and second input terminals of the differential amplifier when the first switching element is in the interruption state.

Abstract: A gas sensor system includes a gas sensor capable of producing an output signal responsive to the concentration of a specific gas component in measurement gas, a gas concentration determination device that makes electrical connections to the gas sensor and determines the concentration of the specific gas component according to the output signal of the gas sensor, a failure detection device that detects a potential failure in any one of the electrical connections, a sensor temperature determination device that judges whether the gas sensor has been cooled to a predetermined temperature or lower with reference to a sensor temperature parameter and a failure identification device that, when the gas sensor has been cooled to the predetermined temperature or lower, outputs a diagnosis signal to the gas sensor, measures potentials of the electrical connections under the diagnosis signal and identifies in which of the electrical connections the potential failure is occurring based on the measured potentials.

Abstract: In a Czochralski (CZ) single crystal puller equipped with a cooler and a thermal insulation member, which are to be disposed in a CZ furnace, smooth recharge and additional charge of material are made possible. Further, elimination of dislocations from a silicon seed crystal by use of the Dash's neck method can be performed smoothly. To these ends,there is provided a CZ single crystal puller, wherein a cooler and a thermal insulation member are immediately moved upward away from a melt surface during recharge or additional charge of material or during elimination of dislocations from a silicon seed crystal by use of the Dash's neck method.

Abstract: A method for manufacturing a single crystal semiconductor, in which, in a process of pulling up the single crystal semiconductor from melt for growing it, an impurity is incorporated more uniformly into the single crystal semiconductor so that a variation in impurity concentration across the semiconductor wafer surface can be reduced, and thus, the planarity of the wafer can be improved. In the process of pulling-up the single crystal semiconductor (6), fluctuation in a pulling-up speed is controlled, whereby the variation in concentration of the impurity in the single crystal semiconductor (6) is reduced. Especially, a width of speed fluctuation (?V) in 10 seconds is adjusted to less than 0.025 mm/min. Furthermore, in carrying out the control for adjusting the pulling-up speed such that a diameter of the single crystal semiconductor (6) becomes a desired diameter, a magnetic field having strength of 1,500 gauss or more is applied to the melt (5).

Abstract: A single crystal semiconductor manufacturing method for realizing a dislocation-free single crystal while not varying or hardly varying electric power supplied to a heater when and after a seed crystal comes into contact with a melt. The allowable temperature difference ?Tc not causing dislocation in the seed crystal is determined according to the concentration (C) of the impurities added to the seed crystal (14) and the size (diameter D) of the seed crystal (14). When the seed crystal (14) comes into contact with the melt (5), electric power supplied to a bottom heater (19) is fixed, and a magnetic field produced by a magnet (20) is applied to the melt (5). Electric power supplied to a main heater (9) is controlled so that the temperature at the surface of the melt (5) which the seed crystal (14) comes into contact with may be a target value. After the seed crystal (14) comes into contact with the melt (5), single crystal silicon is pulled up without performing a necking process.

Abstract: A process for producing a single-crystal semiconductor and an apparatus therefor. A single-crystal semiconductor of large diameter and large weight can be lifted with the use of existing equipment not having any substantial change thereto while not influencing the oxygen concentration of single-crystal semiconductor and the temperature of melt and while not unduly raising the temperature of seed crystal. In particular, the relationship (L1, L2, L3) between the allowable temperature difference (?T) and the diameter (D) of seed crystal (14) is preset so that the temperature difference between the seed crystal (14) at the time the seed crystal (14) is immersed in the melt and the melt (5) falls within the allowable temperature difference (?T) at which dislocations are not introduced into the seed crystal (14). In accordance with the relationship (L1, L2, L3), the allowable temperature difference (?T) corresponding to the diameter (D) of seed crystal (14) to be immersed in the melt is determined.

Abstract: Using a gas detection voltage Vs output from a terminal CU, a determination is made at to whether, after startup of an air-fuel ratio detection apparatus (1), a full-range air-fuel ratio sensor (10) has reached a semi-activated state in which a determination can be made as to whether the air-fuel ratio is on the rich or lean side based on a change in a gas detection signal Vic. After determining that the sensor has reached the semi-activated state, the signal Vic is compared with a threshold to determine whether the air-fuel ratio is on the rich or lean side. In the apparatus (1), the potential difference between an outer pump electrode of a pump cell (14) and a reference electrode of an oxygen concentration measurement cell (24) is obtained via a first differential amplification circuit (53) as the gas detection signal Vic, the signal Vic being highly responsive to a change in air-fuel ratio of exhaust gas.

Abstract: A sensor control apparatus comprising an air/fuel ratio sensor having a sensor cell with a pair of electrodes, a current source capable of supplying a predetermined current between the electrodes, a current control section that turns on/off the current source, a voltage detecting section that detects voltages generated between the electrodes at respective times when the current source is turned on and off, a differential voltage detecting section that detects a differential voltage between the voltages that are generated at the respective times when the current source is turned on and off, a first voltage comparing section that compares the differential voltage with a first threshold voltage, and a half-activated state determining section that determines that the sensor cell has reached a half-activated state when the differential voltage is lower than the first threshold voltage. A sensor control method is also provided.

Abstract: A temperature sensor control apparatus includes a reference potential section, a driving potential section set to a driving electric potential, a temperature sensor configured to vary a resistance in accordance with a temperature, and disposed between the reference potential section and the driving potential section, a conduction path, two reference resistance elements each connected in series with the temperature sensor, a potential controlled point disposed in the conduction path between the reference resistance elements, a potential setting section configured to set an electric potential of the potential controlled point to the driving electric potential; and a resistance switching control section configured to control the potential setting section to switch the electric potential of the potential controlled point, and to switch each of the reference resistance elements to one of an energized state and a deenergized state.

Abstract: A production device and production method for carbon fibers of the present invention is utilized to reliably obtain a connecting portion having a high process passing property with a simple mechanism so as to achieve a continuous operation and improve a firing process operability for achieving a low cost. A pair of yarn gripping devices for overlaying precursor fiber yarns to be connected one upon another and gripping the overlaid ends is provided, and a fluid processing unit for applying an entangling process by jetting a plurality of rows of fluid in along a yarn length direction is provided between the pair of yarn gripping devices. A plurality of discontinuous thread handling areas of the precursor fiber yarns in a fluid jet area of the fluid processing unit having fluid jet holes are disposed at predetermined intervals.

Abstract: A sensor control device is connected with a plurality of exhaust sensors including an NOx sensor to be disposed around a catalyst, and is constructed such that a plurality of drive control circuits to be connected in a one-to-one relationship with the individual gas sensors are disposed in one casing. The sensor control device is provided with a communication output section that outputs signals through a digital communication line so that the signal transmissions/receptions with an ECU may be executed through the digital communication line. This digital communication line is physically a one-system cable but can transmit and receive signals of a plurality of kinds with predetermined communication protocols.

Abstract: A gas detection apparatus including a gas sensor element and a gas-sensor control circuit. The gas sensor element includes at least one sensor cell including a solid electrolyte member and a pair of electrodes, and external connection terminals electrically connected to the electrodes. The gas-sensor control circuit includes control terminals electrically connected to respective external connection terminals of the gas sensor element, an inspection current supply circuit for supplying an inspection current to an inspected terminal, which is a control terminal to be inspected for presence or absence of a short circuit to a predetermined potential, an inspection potential measurement circuit for measuring the potential of the inspected terminal, and an uninspected terminal impedance increasing circuit for increasing the impedance of the gas-sensor control circuit as viewed from an uninspected terminal, which is a control terminal other than the inspected terminal.

Abstract: A gas sensor control unit (1) including a single signal-switching and outputting circuit (33) adapted for switching and outputting plural signals transmitted from plural gas sensors (8,9).

Abstract: In an activation state of a sensor device, when voltage on the connection points between the sensor device and the sensor control circuit becomes a preset abnormal value, electric cut off is made between the sensor control circuit and the connection point. Then, the delivery of power to the heater is ceased to lower the temperature of the cells to a below of an activation temperature, thereby increasing the internal resistance of the cell. Thereafter, the sensor control circuit supplies to the sensor device a current in a degree not to damage the sensor device, to detect voltages on the connection points at that time. By comparing between the voltages on the respective connection points detected, a content and location of abnormality occurred is identified for the sensor device.

Abstract: The present invention is to produce a silicon crystal wherein the boron concentration in the silicon crystal and the growth condition V/G are controlled so that the boron concentration in the silicon crystal is no less than 1×1018 atoms/cm3 and the growth condition V/G falls within the epitaxial defect-free region ?2 whose lower limit line LN1 is the line indicating that the growth rate V gradually drops as the boron concentration increases. Further, the present invention is to produce a silicon wafer wherein the boron concentration in the silicon crystal and the growth condition V/G are controlled so as to include at least the epitaxial defect region ?1, and the heat treatment condition of the silicon crystal and the oxygen concentration in the silicon crystal are controlled so that no OSF nuclei grow to OSFs.

Abstract: In a Czochralski (CZ) single crystal puller equipped with a cooler and a thermal insulation member, which are to be disposed in a CZ furnace, smooth recharge and additional charge of material are made possible. Further, elimination of dislocations from a silicon seed crystal by use of the Dash's neck method can be performed smoothly. To these ends, there is provided a CZ single crystal puller, wherein a cooler and a thermal insulation member are immediately moved upward away from a melt surface during recharge or additional charge of material or during elimination of dislocations from a silicon seed crystal by use of the Dash's neck method.

Abstract: In a Czochralski (CZ) single crystal puller equipped with a cooler and a thermal insulation member, which are to be disposed in a CZ furnace, smooth recharge and additional charge of material are made possible. Further, elimination of dislocations from a silicon seed crystal by use of the Dash's neck method can be performed smoothly. To these ends, there is provided a CZ single crystal puller, wherein a cooler and a thermal insulation member are immediately moved upward away from a melt surface during recharge or additional charge of material or during elimination of dislocations from a silicon seed crystal by use of the Dash's neck method.