Denso Corporation

Nippondenso Co., Ltd.

National Institute of Advanced Industrial Science and Technology

Yuji Kimura

Mitsuhiro Kataoka

Kinya Atsumi

Susumu Sobue

Katsunori Abe

Noriyuki Matsushita

Tetsuo Toyama

Takeshi Matsui

Eiichi Okuno

Noriaki Shirai

Yoshiki Ueno

Satoshi Yamasaki

Hiromitsu Kato

Katsuhiro Morikawa

Daisuke Takeuchi

Shoichi Kawai

Katsuji Kosaka

Yoshinori Otsuka

Michiyo Mizutani

A heat transfer device that includes a thermionic power generator, a wiring, a load circuit, and a switch circuit. The thermionic power generator includes an emitter electrode and a collector electrode facing each other with an inter-electrode gap distance, and converts heat energy into electric energy by capturing, with the collector electrode, a thermoelectron that is emitted from the emitter electrode. The wiring electrically connects the emitter electrode and the collector electrode. The load circuit is connected to an electric current path of by wiring between the emitter electrode and the collector electrode. The switch circuit switches between an ON state and an OFF state.

Heat transfer device, temperature controller, internal combustion engine, exhaust system thereof, and melting furnace

A thermionic power generator includes an emitter generating thermions and a collector collecting the thermions. The emitter includes an emitter substrate having an electric conductivity, a low resistance layer stacked to the emitter substrate and made of an n-type diamond semiconductor that includes phosphorus as a donor, and an electron emission layer stacked to the low resistance layer and made of an n-type diamond semiconductor that includes nitrogen as a donor. The collector includes a collector substrate having an electric conductivity and is disposed opposite to the emitter via a clearance. The electron emission layer has a thickness equal to or less than 40 nm.

Thermionic power generator

In a method of manufacturing an electrode of a thermionic converter, a carbide layer is formed on a base material by a vapor synthesis, an N-type diamond layer doped with a donor impurity is formed on the carbide layer by a vapor synthesis, and a surface of the N-type diamond layer is terminated with hydrogen. The base material is made of a metal, and the carbide layer is made of a metal carbide.

Thermionic converter and manufacturing method of electrode of thermionic converter

A thermionic generator for converting thermal energy to electric energy includes: an emitter electrode for emitting thermal electrons from a thermal electron emitting surface when heat is applied to the emitter electrode; a collector electrode facing the emitter electrode spaced apart from the emitter electrode by a predetermined distance, and receiving the thermal electrons from the emitter electrode via a facing surface of the collector electrode; and a substrate having one surface. The emitter electrode and the collector electrode are disposed on the one surface of the substrate, and are electrically insulated from each other. The thermal electron emitting surface and the facing surface are perpendicular to the one surface.

Thermionic generator

A thermionic converter for converting thermal energy to electrical energy includes an emitter and a collector. The emitter emits thermionic electrons upon receipt of heat from a heat source. The emitter is made of a first semiconductor material to which a first semiconductor impurity is doped with a first concentration. The collector is spaced and opposite to the emitter to receive the thermionic electrons emitted from the emitter so that the thermal energy is converted to electrical energy. The collector is made of a second semiconductor material to which a second semiconductor impurity is doped with a second concentration less than the first concentration.

Thermionic converter

A scanning device periodically changes the direction of the transmission of an electromagnetic wave from an electromagnetic wave generating device. A first driving device operates for repetitively driving the electromagnetic wave generating device a plurality of times per one period of the change of the direction by the scanning device, and thereby for repetitively transmitting a distance measurement electromagnetic wave. A second driving device operates for, before the first driving device drives the electromagnetic wave generating device, driving the electromagnetic wave generating device and thereby transmitting a judgment electromagnetic wave having an energy smaller than that of the distance measurement electromagnetic wave. An obstacle judging device permits the first driving device to drive the electromagnetic wave generating device next in cases where a detected obstacle is absent, and inhibits the first driving device from driving the electromagnetic wave generating device next in cases where a detected obstacle is present.

Distance measurement apparatus

In performing an light emitting operation using a plurality of semiconductor light-emitting devices, these semiconductor light-emitting devices are lighted up such that the driving current is lessened and the life time of the devices is prevented from being shortened and lights can be emitted to a remote site without reducing an amount of lights. Semiconductor laser devices to , which emit lights through independent lenses to , are connected in series to each other and connected to a signal generating circuit , serving as a power supply, so as to perform pulse lighting, whereby making it possible to light up three semiconductor laser devices simultaneously at a driving current corresponding to one semiconductor laser device. A package of semiconductor laser devices to comprises three lead terminals, and an electrical connection to two lead terminals, which are electrically insulated from a metallic base, is established. If a light collection point P is positioned in the midway of the detection distance range, the shifting quantity of the laser beams is minimized over substantially the entire area so that the amount of lights can be suppressed.

Semiconductor light projection apparatus and distance measurement apparatus

A stack type semiconductor laser device, which has a large overlapped area of beam patterns made by laser beams irradiated from a plurality of semiconductor laser elements, is disclosed. A first semiconductor laser element is formed on an N-type semiconductor substrate and is bonded to a surface of a pedestal at the side of an N-type electrode thereof through a solder layer. On the other hand, a second semiconductor laser element is differently formed on a P-type semiconductor substrate, and an N-type electrode thereof is bonded to a P-type electrode of the first semiconductor laser element through a solder layer in such a way that the laser beam irradiation planes of both semiconductor laser elements face in the same direction.

Stack type semiconductor laser device

A material and method for bonding a semiconductor device to a pedestal, which can obtain a sufficient bonding strength and stable electric contact, are disclosed. On an n-type electrode constituting an ohmic electrode for a semiconductor laser device are formed a Ni layer and an Au-Sn solder layer. Then, the solder layer is melted and bonded to a heat sink provided with Au-plating. The film thickness of the Ni layer is set to approximately 500 .ANG. or more. When the solder layer is melted, Ni in the Ni layer diffuses into the solder layer and Sn in the solder layer diffuses into the Ni layer. By this mutual diffusion, bonding strength and wettability between the semiconductor device and pedestal can be improved. In addition, by setting the composition ratio of Ni layer to the Au-Sn solder layer to 1.3 wt % or more and under 10 wt %, bonding can be performed at a lower melting point and concurrently a higher bonding strength can be obtained.

Bonding material and bonding method for electric element

A high-output semiconductor laser element has one of a Cr/Pt/Au electrode and Cr/Ni/Au electrode as a P-type electrode to provide an electrode construction that is robust with respect to heat, high in reliability and stable for a long period of time. The P-type electrode is disposed on an N-type substrate via an epitaxial layer and defines a stripe 41 having a width of 100 .mu.m or more.

High output semiconductor laser element having robust electrode structure

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.

Growing community of inventors

Nagoya, Japan

Yuji Kimura