A power semiconductor device includes trenches disposed in a first base layer of a first conductivity type at intervals to partition main and dummy cells, at a position remote from a collector layer of a second conductivity type. In the main cell, a second base layer of the second conductivity type, and an emitter layer of the first conductivity type are disposed. In the dummy cell, a buffer layer of the second conductivity type is disposed. A gate electrode is disposed, through a gate insulating film, in a trench adjacent to the main cell. A buffer resistor having an infinitely large resistance value is inserted between the buffer layer and emitter electrode. The dummy cell is provided with an inhibiting structure to reduce carriers of the second conductivity type to flow to and accumulate in the buffer layer from the collector layer.

Power semiconductor device

In embodiments of a multiple waveguide imaging structure, a wearable display device includes left and right imaging units of respective display lens systems to generate an augmented reality image that includes a virtual image. Each of the left and right imaging units include a first waveguide for see-through viewing at a first field of view, where the first waveguide includes a first polarizing beam splitter to reflect light that enters at a first polarization orientation angle and pass through the light that enters at a second polarization orientation angle. Each of the left and right imaging units also include at least a second waveguide for see-through viewing at a second field of view, where the second waveguide includes a second polarizing beam splitter to reflect the light that enters at the first polarization orientation angle and pass through the light that enters at the second polarization orientation angle.

Multiple waveguide imaging structure

In embodiments of waveguide optics focus elements, an imaging structure includes a waveguide for viewing of an environment that is viewable with the imaging structure. The waveguide transmits light of a virtual image that is generated to appear as part of the environment for augmented-reality imaging or virtual-reality imaging. The imaging structure also includes one or more focus elements that are integrated in the waveguide and switchable to focus the virtual image at a focus depth that approximately correlates to a focal distance of the environment. The focus elements can each be implemented for a different focus depth of the virtual image, and the focus depth is adjustable based on a combination of the focus elements being switched-on or switched-off.

Waveguide optics focus elements

A sealable module, cooled electronic system and method are described relating to cooling a heat generating electronic device. The sealable module is adapted to be filled with a first cooling liquid and a heat transfer device having a conduction surface defines a channel for receiving a second cooling liquid. In one embodiment, at least a portion of the conduction surface or housing is shaped in conformity with the shape of the electronic component. Control of the second cooling liquid is also described. Transferring heat between the second cooling liquid and a third cooling liquid features in embodiments. A method of filling a container with a cooling liquid is further detailed.

Cooled electronic system

A heat dissipation device includes a primary heat sink ( 10 ) contacting a central processing unit and a secondary heat sink ( 20 ) attached on heat-generating electronic components adjacent the central processing unit. The primary heat sink includes a base ( 12 ) and a heat-dissipation portion ( 14 ) disposed on a middle of the base. The secondary heat sink includes a substrate ( 22 ) and a plurality of fin assemblies ( 24 ) arranged on the substrate. The base is laid on the substrate with the fin assemblies arranged around the heat-dissipation portion. The primary heat sink is partly superposed on the secondary heat sink with a compact structure. The heat-dissipation portion can simultaneously dissipate heat from the central processing unit and its adjacent heat-generating electronic components.

Heat dissipation device

IGBT modules, bus bars and capacitors in an inverter main circuit are secured on the front face of a heat sink and at the back side of the heat sink a water cooling channel is formed to cool the IGBT modules. The bus bars and the capacitor, thereby the size of an inverter device used in an electric car is reduced and the duration thereof is prolonged.

Inverter device with cooling arrangement therefor

A cooling apparatus having a plurality of heat pipes is improved to reduce the condensation capacity of selected heat pipes when ambient air temperature is low, so as to facilitate start-up of the cooling apparatus from a state in which the working fluid in the heat pipes has been frozen. The cooling apparatus has a block of a high heat conductivity in which one end of each heat pipe serving as an evaporation section of the heat pipe is embedded. Heat radiation fins are attached to portions of the heat pipes exposed from the block, so that the exposed portions of the heat pipes serve as condensation sections of the respective heat pipes. There are two types of heat radiation fins: a first type of fins which are attached to all the heat pipes and a second type of fins which are attached only to selected heat pipes.

Heat-pipe type cooling apparatus

A liquid cooling system, comprises: heat-receiving jacket 7, thermally connected with a heat-generation element, a pump attached onto a radiator 1 a, and a tank portion 2 on the radiator 1 a, wherein a coolant liquid is circulated between the heat-receiving jacket 7 and the radiator 1 a by means of the pump 8, thereby obtaining the liquid cooling system for an electronic apparatus, being suitable for small-sizing and a thin-type, while maintaining high reliability thereof.

Liquid cooling system

A wire bonding method and apparatus implement the flatly thinner plastic deformation for the joint section of a wire, which has a diameter ranging 100-600 μm, on its feed side, feed out and position the flatly deformed wire joint section to a target joint surface, and join the wire to it by pressing the positioned wire joint section, with vibration being applied, onto the joint surface with a ultrasonic wire bonder. A high-power semiconductor device fabricated based on this scheme has a long life of wire joints.

Wire bonding method and apparatus, and semiconductor device

In an electric power conversion/inversion apparatus, including, such as an inverter therein, for obtaining reduction in circuit inductance and wiring resistance therein by bringing small as a whole, having good installability and high reliability and efficiency of electric power conversion, as well, semiconductor chips 1 are disposed, being put between a positive input bus bar 14 p and a negative input bus bar 14 n and plural output bus bars 18 at crossing positions thereof, and are connected electrically and thermally, to the positive input bus bar 14 p in a pole direction consistent therewith while to the negative input bus bar 14 n in a pole direction consistent therewith, and further to the common output bus bars 18 in pole directions being different from side by side.

Osamu Suzuki

Papers

Inverter device with cooling arrangement therefor

Heat-pipe type cooling apparatus

Liquid cooling system

Wire bonding method and apparatus, and semiconductor device

Electric power conversion/inversion apparatus