Abstract: In a method of manufacturing a semiconductor device having a memory mat portion in which an active region and a field region are formed densely, after a polishing stopper film is deposited on a semiconductor substrate, there are formed grooves by etching a polishing stopper film of a field region and the semiconductor substrate. Then, after an insulating film is deposited so as to fill the grooves, then insulating film is partly removed from the memory mat portion by etching. Under this state, the insulating film is chemically mechanically polished until the polishing stopper film is exposed. The film thickness of the polishing stopper film on the active region can be reduced, and an electrical element isolation characteristic of the field region can be improved.

Abstract: Disclosed herein is an evaporative emission control system which can prevent changes in fuel component in the fuel tank and vacuum boiling in the fuel pump to thereby accurately control the air-fuel ratio to a desired value and ensure smooth supply of the fuel. The control system includes an evaporative fuel passage for connecting a fuel tank and an intake system of an internal combustion engine, and a control valve is provided in the evaporative fuel passage for opening and closing the evaporative fuel passage. It is determined whether or not a pressure in the tank is higher than or equal to a pressure value obtained by adding a pressure in the intake system. If the pressure in the tank is higher than or equal to the pressure value, the opening operation of the control valve is enabled.

Abstract: A semiconductor device produced by forming an oxide film on a substrate, heat treating the oxide film at a temperature of 800° C. or higher in an inert atmosphere, followed by conventional steps for formation of a transistor, is improved in electrical reliability due to relaxation of stress generated in the oxide film or in the surface of substrate.

Abstract: A method for manufacturing a semiconductor device includes the steps of (1) forming a pad oxide film of 5 nm or more on a circuit forming surface of a semiconductor substrate; (2) forming an oxidation inhibition film on the pad oxide film; (3) forming grooves of a given depth with the oxidation inhibition film as a mask; (4) receding the pad oxide film; (5) oxidizing the grooves formed on the semiconductor substrate in the range of 0<C≦0.88t-924 in which the oxidizing atmosphere is dry oxidation (H2/O2≈0), the oxygen partial pressure in the air corresponding to the oxygen partial pressure ratio is C %, and the oxidizing temperature is t (° C.

Abstract: Disclosed herein is an evaporative emission control system which can properly control the ratio between a tank purge amount and a canister purge amount to realize quick pressure reduction in a fuel tank and ensuring the storage capacity of a canister in a well balanced fashion. A target pressure in controlling the pressure in the fuel tank at a negative pressure and a detected pressure in the fuel tank are compared with each other. When the difference between the target pressure and the detected pressure is large, tank purge is preferentially carried out to open a tank pressure control valve. When the detected pressure is in the vicinity of the target pressure, canister purge is preferentially carried out to purge the evaporative fuel stored in the canister.

Abstract: A semiconductor device having a highly reliable groove isolation structure with a desired radius of curvature formed at the groove upper edge and without formation of any step, there is produced by reducing the stress generation around the groove upper edge of an element isolation groove on a semiconductor substrate, thereby optimizing the shape of an element isolation groove and making the device finer and improving the device electric characteristics.

Abstract: A mobile communication system includes a mobile terminal, a base station, and a mobile switching station. The mobile terminal, the base station and the mobile switching station are constructed so that communication information and control information are transferred by an asynchronous transfer mode (ATM) cell between the mobile terminal and the base station, between mobile switching station and the base station.

Abstract: A method for manufacturing a semiconductor device includes the steps of (1) forming a pad oxide film of 5 nm or more on a circuit forming surface of a semiconductor substrate; (2) forming an oxidation inhibition film on the pad oxide film; (3) forming grooves of a given depth with the oxidation inhibition film as a mask; (4) receding the pad oxide film; (5) oxidizing the grooves formed on the semiconductor substrate in the range of 0<C≦0.88t−924 in which the oxidizing atmosphere is dry oxidation (H2/O2≈0), the oxygen partial pressure in the air corresponding to the oxygen partial pressure ratio is C %, and the oxidizing temperature is t (° C.

Abstract: There is provided a fuel supply control system for an internal combustion engine, which is capable of controlling fuel cutoff according to an amount of oxygen stored in a catalytic converter to thereby enhance the purification rate of the catalytic converter while maintaining excellent fuel economy, thereby making it possible to improve exhaust emission characteristics. An amount of oxygen stored in the catalytic converter 13 arranged in an exhaust pipe 12 of an engine 3 is estimated (steps S1 to S29). A deceleration condition of the engine is detected (steps S35, S36). When the deceleration condition is detected, supply of fuel to the engine is cut off (step S41). The cutoff of fuel supply is controlled based on the oxygen storage amount OSC (steps S31, S32, S40, S41).

Abstract: A push button switch covering member of a silicone rubber is imparted with excellent resistance against stain deposition and abrasive wearing by providing a protective overcoating layer of a urethane resin-based coating composition capable of being cured by forming urethane linkages between isocyanate groups of a polyisocyanate compound and hydroxy groups of a polyhydroxy compound. The coating procedure with the coating composition on the surface of a silicone rubber-made covering member is preceded by a plasma treatment so as to activate the surface resulting in an increased adhesive bonding strength between the silicone rubber body and the coating layer. The improvement is more remarkable when the plasma-activated surface is subjected to a priming treatment with a silane coupling agent and coating with the coating composition is undertaken as soon as possible or within 60 minutes after completion of the plasma treatment.

Abstract: In an exhaust gas purifying apparatus of the present invention, oxygen sensors 18 and 20 are respectively located upstream, a close coupled three-way catalyst 14 positioned at the upstream end of an exhaust system, and downstream, in a under floor three-way catalyst 17 positioned at the downstream end. When an output VO2 of the oxygen sensor 20 exceeds a predetermined voltage VO2H2, the first correction coefficient KCMDLS is calculated in accordance with the output VO2 (S12 and S13). And when VO2≦VO2H2 is established, in accordance with the engine operating state the second correction coefficient KVMDR is set to a predetermined value KVMDR0 that is slightly greater than 1.0 (S16 to S18), and the target air-fuel ratio coefficient KCMD is corrected by using the correction coefficients KCMDLS and KCMDR (S21).

Abstract: A semiconductor device having a highly reliable groove isolation structure with a desired radius of curvature formed at the groove upper edge and without formation of any step, there is produced by reducing the stress generation around the groove upper edge of an element isolation groove on a semiconductor substrate, thereby optimizing the shape of an element isolation groove and making the device finer and improving the device electric characteristics.

Abstract: In a method of manufacturing a semiconductor device having a memory mat portion in which an active region and a field region are formed densely, after a polishing stopper film is deposited on a semiconductor substrate, there are formed grooves by etching a polishing stopper film of a field region and the semiconductor substrate. Then, after an insulating film is deposited so as to fill the grooves, the insulating film is partly removed from the memory mat portion by etching. Under this state, the insulating film is chemically mechanically polished until the polishing stopper film is exposed. The film thickness of the polishing stopper film on the active region can be reduced, and an electrical element isolation characteristic of the field region can be improved.

Abstract: In a process for the fabrication of a semiconductor integrated circuit using a double-side mirror-polished wafer or the like, at the portion of a notch 10 of a notched wafer 1, a chamfered angle &thgr;11 of the first chamfered portion 11 formed at the inner periphery of the first primary surface 3 is set smaller than the chamfered angle &thgr;12 of the second notch chamfered portion 12 of the second primary surface 4 and the chamfered width L11 is set larger than the chamfered width L12, whereby the obverse and reverse of the wafer are discriminated by optically discriminating the first notch chamfered portion and the second notch chamfered portion using reflected light, thereby making it certain to fabricate IC on the surface of the wafer and to use the reverse for its handling.

Abstract: In each sampling period, sample data and a count value WA of a ring buffer counter 11 are supplied to a RAM 202 through a bus control circuit 14 as write data and a write address. Each cache block stored in a data buffer DB.sub.0 and so on is used for executing an FIR filtering operation. As an amount of unused sample data in the cache block is decreased, subsequent cache blocks used for a subsequent FIR filtering operation are supplemented to the data buffers DB.sub.0 and so on by the cache counter units CC.sub.0 and so on.

Abstract: A shallow groove isolation structure (SGI) electrically insulates adjoining transistors on a semiconductor substrate. A pad oxide film is formed on the semiconductor substrate and an oxidation inhibition film is formed on the pad oxide film. Parts of the oxide inhibition film and pad oxide film are removed to form the groove. In particular, the pad oxide film is removed from an upper edge of the groove within a range of 5 to 40 nm. A region of the groove is oxidized in an oxidation environment with a cast ratio of hydrogen (H.sub.2) to oxygen (O.sub.2) being less than or equal to 0.5. At this ratio, the oxidizing progresses under low stress at the upper groove edges of the substrate thereby enabling rounding of the upper groove edges without creating a level difference at or near the upper groove edge on the substrate surface.

Abstract: An air-fuel ratio control system for an internal combustion engine is provided, which includes an oxygen concentration sensor arranged in the exhaust system and having an output characteristic that an output thereof is substantially proportional to concentration of oxygen present in exhaust gases from the engine. An ECU is responsive to the output of the oxygen concentration sensor, for carrying out feedback control of the air-fuel ratio of a mixture supplied to the engine so as to make the air-fuel ratio equal to a desired air-fuel ratio. An activated state of the oxygen concentration sensor is detected. Correction of the air-fuel ratio of the mixture by the feedback control is limited, depending upon the detected activated state of the oxygen concentration sensor.

Abstract: A method that detects an air-fuel ratio in each cylinder of an internal combustion engine by properly setting a cycle of detecting an element resistance of an A/F oxygen concentration sensor. Although an actual A/F signal is at the stoichiometric ratio in each cylinder at exhaust timing cycle in a practical engine rotational speed range, the ratio is largely deviated to the rich side in the #1 cylinder. The first element resistance detection timing cycle coincides with generation timing of the actual A/F signal, so that the A/F signal cannot be detected. When the element resistance detection timing cycle is preset so as to be longer than the exhaust timing cycle, the second actual A/F signal detection timing for the #1 cylinder does not coincide with the element resistance detection timing. Consequently, the actual A/F signal of the #1 cylinder can be detected as an A/F signal by the A/F sensor.

Abstract: A silicon oxide film 2 which is exposed from a side wall of a groove 4a is etched to displace the silicon oxide film 2 backward toward an active region. The displacement amount is set to be equal to or more than a film thickness (Tr) of a silicon oxide film 5 to be formed on an inner wall of the groove 4a in a later thermal oxidation step and equal to or less than twice the film thickness (Tr) thereof. A shoulder portion of the groove 4a can be rounded by a low-temperature heat treatment at 1000.degree. C. or less, by controlling a heat treatment period such that the film thickness (Tr) of the silicon oxide film 5 is more than the film thickness (Tp) of the silicon oxide film 2 and equal to or less than three times the film thickness (Tr) thereof (Tp<Tr.ltoreq.

Abstract: Over the principal surface of a semiconductor substrate body containing an impurity of a predetermined conduction type, there is formed an epitaxial layer which contains an impurity of the same conduction type as that of the former impurity and the same concentration as the designed one of the former impurity. After this, there are formed a well region which has the same conduction type as that of said impurity and its impurity concentration gradually lowered depthwise of said epitaxial layer. The well region is formed with the gate insulating films of MIS.FETs.