Nippon Soken, Inc.

Toyota Jidosha Kogyo Kabushiki Kaisha

Nippondenso Co., Ltd.

Research Development Corporation of Japan

Yoshiki Ueno

Tadashi Hattori

Minoru Nishida

Mamoru Kobashi

Takashi Taguchi

Susumu Sato

Takasi Taguchi

Tooru Kawase

Kazuhiko Miura

Kazuoki Matsugatani

Takakazu Kawabata

Masamichi Shibata

Kinya Atsumi

Yuji Kimura

Noriyuki Matsushita

Katsunori Abe

Kouichi Hoshino

Kunio Makita

Masaaki Kurii

Takuya Kouya

Osamu Kashima

Tooro Kawase

Toru Kawase

A first semiconductor layer and a second semiconductor layer are laminated on a semiconductor wafer in that order. A resist pattern having an opening is formed on the second semiconductor layer. The second semiconductor layer is etched through the opening in the formed resist pattern to expose the first semiconductor layer. A surface oxide film is formed on the exposed surface of the first semiconductor layer and then selectively etched away. Alternatively, the exposed surface of the first semiconductor layer is subjected to a separate oxidization treatment and the resulting surface oxide film is selectively removed in the subsequent etching.

Semiconductor wafer etching process and semiconductor device

The semiconductor laser device provides a large output laser beam approximating a circular shape. Formed on an n-GaAs substrate is an n-GaAs layer, further thereon in mesa type with an n-Al.sub.0.4 Ga.sub.0.6 As clad layer, an n-Al.sub.0.2 Ga.sub.0.8 As optical guide layer, an active layer formed of Al.sub.0.2 Ga.sub.0.8 As/GaAs multi-quantum well structure, a p-Al.sub.0.2 Ga.sub.0.8 As optical guide layer, a p-Al.sub.0.4 Ga.sub.0.6 As clad layer, and a p-GaAs layer. A thickness of the active layer is made equal to 127.5 nm, and a sum of thicknesses of the active layer and the optical guide layers and is made equal to or more than 1.5 .mu.m. On the n-GaAs layer and the upper surface of mesa shaped portion are formed an insulating film and a p-type electrode, the stripe width of which is equal to 400 .mu.m.

Semiconductor laser device

A pseudomorphic HEMT of a structure which prevents the distribution of 2DEG in the channel layer from being concentrated near the hetero-interface relative to a doping layer and which, at the same time, enables the thickness of the channel layer to which distortion is imparted to be decreased. In an n-InAlAs/InGaAs pseudomorphic structure grown on an InP substrate 1, an InGaAs spacer layer 4 having an In composition ratio smaller than that of an InGaAs channel layer 3 is inserted in an InAlAs/InGaAs hetero-interface. The InGaAs channel layer 3 has an In composition ratio of 0.80 to exhibit a high mobility. Another InAlAs buffer layer 2, spacer layer 5 and doping layer 6 have an In composition ratio of 0.52 which is in lattice-match with the substrate, and InGaAs spacer layer 4 and cap layer 7 have an In composition ratio of 0.53 which is in lattice-match with the substrate. This constitution makes it possible to control the two-dimensional electron gas and to further increase the mobility.

Compound semiconductor substrate having a hetero-junction and a

A compound semiconductor device including a semiconductor substrate having (100) plane as a crystal growth plane, a first semiconductor layer as an electron traveling layer and a second semiconductor layer for supplying electrons to the electron traveling layer. The first semiconductor layer is formed on the semiconductor substrate and has a different lattice constant from the semiconductor substrate so that a first strain is applied in the first semiconductor layer in a first strain direction. The second semiconductor layer is formed on the first semiconductor layer and has a different lattice constant from the first semiconductor layer to thereby apply a second strain to the second semiconductor layer. The second strain has a direction that is inverse to the first strain direction. In addition, the thickness of the semiconductor layer is defined so as to compensate for the first strain applied to the first semiconductor layer by the second strain applied to the second semiconductor.

Compound semiconductor device for reducing the influence of resistance

An antiglare mirror for an automobile including a metal layer for reflecting incident light and a liquid crystal layer in front of the reflecting surface of the metal layer. The reflected light is colored by forming a transparent dielectric layer on the reflecting surface of the metal layer. The transparent dielectric layer has a higher refractivity than that of the liquid crystal layer. A desired color tone is obtained by selecting the thickness of the transparent dielectric layer.

Antiglare mirror for an automobile

A reflecting mirror for use as a rearview mirror in an automobile, the mirror having a plurality of thin layers arranged on a glass plate. One of the layers is made of a transparent dielectric material having a refractive index which is not less than a refractive index of WO.sub.2 and the other is made of a metal material having a reflecting factor ranging between 50-70%. The light introduced into the mirror is reflected at different borders formed in the mirror between the layers so as to provide lights of different phases. Therefore, there is an interference, and, consequently, the mirror provides a certain selected tone in accordance with the value of the optical thickness of the transparent dielectric layer, resulting in an anti-glare effect and a deep color.

Reflecting mirror for an automobile

A reflecting mirror for use as a rearview mirror in an automobile, the mirror having a plurality of thin layers arranged on a glass substratum plate. One of the layers is made so that it has an electric resistance, a pair of electrodes being connected thereto. An electric current is applied in order to generate heat to remove cloudiness or frost on the reflecting surface of the mirror. The mirror may also have a heat wave-reflecting layer for reflecting heat waves from the electric resistance layer.

Defrostable outside rear view mirror for an automobile

A heat-blocking glass comprising: a first layer of infrared rays-blocking film of any thickness formed on a substrate; a plurality of intermediate layers from a second to a (2n+2)th layer (n: positive integral) stacked on said first layer, the optical thickness of each intermediate layer being .lambda./4 (.lambda.: design wavelength); and an uppermost (+3)th layer of a .lambda./8 optical thickness. The refractive index of the first layer is smaller than the refractive index of the second layer. The refractive index of each layer from the second layer to the uppermost layer is arranged so that high-refractive-index layers and low-refractive-index layers are alternately stacked, the second layer being disposed as a high-refractive-index layer.

Heat-blocking glass

Heat reflection film

A heat rays reflecting film composed of dielectric thin layers (n.sub.H layers) having a relatively high refractive index and dielectric thin layers (n.sub.L layers) having a relatively low refractive index which are alternately piled on one another, is disclosed. The first layer of the heat rays reflecting film, which contacts with the air is n.sub.L layer and the undermost layer which contacts with the window glass is n.sub.H layer. The optical thickness of the first layer is less than .lambda./4 while that of the other layers is .lambda./4. And the thickness of each layer is expressed by the formula: optical thickness/nv wherein nv is the refractive index for visible rays.

Heat rays reflecting film

A knocking detector for internal combustion engines includes an illumination detector for detecting the illumination intensity of combustion of the air-fuel mixture in the combustion chamber and a knocking discriminator for deciding whether or not a knocking has occurred on the basis of a signal produced from the illumination detector. The illumination detector is provided on the cylinder head of the internal combustion engine and is sensitive only to the light longer in wavelength than the near infrared rays.

Knocking detector for internal combustion engine

A diagnostic apparatus for an internal combustion engine ignition system measures the rise of the secondary voltage at the ignition coil represented by time lapse between initiation of the secondary voltage rising and occurrence of break and the ignition coil primary breaking current value. Results of the measurement are computed to determine stray capacitance existing in the internal combustion engine ignition system and secondary voltage.

Diagnostic apparatus for internal combustion engine ignition system

An ignition system for internal combustion engine, which controls the ignition coil primary current according to the magnitude of the floating capacitance in the secondary side wiring section of the ignition coil, by determining the floating capacitance from the negative slope of rising of the secondary voltage produced in the ignition coil in response to the cutoff of the primary current and the primary cutoff current value, the slope being determined by measuring the period T until the secondary voltage reaches a predetermined voltage value. When the floating capacitance is increased, the primary cutoff current value is increased to increase the coil energy so as to increase the secondary voltage generated in the ignition coil for preventing the generation of a miss-spark.

Device for diagnosing ignition system for use in internal combustion

An air-fuel ratio detecting system is designed to compensate for the effects of temperature changes on the output resistance of an air-fuel ratio sensor adapted to detect the air-fuel ratio of mixture supplied to an engine from the composition of its exhaust gases so as to vary its electric resistance in accordance with the air-fuel ratio. The system further includes a current control circuit for controlling the current supplied to the air-fuel ratio sensor, an average voltage detecting circuit for detecting a rich air-fuel ratio peak voltage and a lean air-fuel ratio peak voltage and obtaining the intermediate voltage therebetween, a bias control circuit responsive to the value of the intermediate voltage so as to adjust the current control amount of the current control circuit, and a comparator responsive to the junction point voltage and the value of the intermediate voltage so as to generate an air-fuel ratio detection signal. Alternatively, the average value of the rich side peak voltage and the ground voltage or the average value of the lean side peak voltage and the supply voltage may be used as the desired intermediate voltage.

Air-fuel ratio detecting system

An air-fuel ratio detecting system detects the air-fuel ratio of the mixture supplied to an engine by means of titania whose electric resistance value varies in response to the oxygen content of the exhaust gases. The titania is connected in series with a reference resistor and a fixed voltage is applied to the junction of the titania and the reference resistor so as to generate a voltage corresponding to a change in the electric resistance of the titania. The detection voltage generated at the junction indicates the air-fuel ratio of the mixture and it is compared with a reference voltage for determining whether the air-fuel ratio is equal to the stoichiometric air-fuel ratio. The electric resistance of the titania varies with its operating temperature and the detection voltage varies correspondingly. To prevent any error in the control of air-fuel ratio due to a change in the temperature-dependent detection voltage, the peak value of the detection voltage which indicates that the air-fuel ratio of the mixture is greater than the stoichiometric ratio is sampled and the reference voltage is changed in response to the peak voltage. A programmable read-only memory is used to allow easy setting of the peak voltage and the reference voltage in a nonlinear relation with each other.

Growing community of inventors

Okazaki, Japan

Yoshiki Ueno