Abstract: A semiconductor device disclosed herein comprises: a first base region which is of a first conductivity type; a second base region which is of a second conductivity type and which is selectively formed on a major surface of the first base region; a stopper region which is of a first conductivity type and which is formed on the major surface of the first base region, the stopper region being a predetermined distance away from the second base region and surrounding the second base region; and a ring region which is of a second conductivity type which is formed on the major surface of the first base region between the second base region and the stopper region, the ring region being spirally around the second base region and electrically connected to the second base region and the stopper region.

Abstract: A semiconductor device comprises a first base layer of a first conductive type which has a first surface and a second surface; a second base layer of a second conductive type which is formed on the first surface; first and second gate electrodes which are formed by embedding an electrically conductive material into a plurality of trenches via gate insulating films, the plurality of trenches being formed such that bottoms of the trenches reach the first base layer; source layers of the first conductive type which are formed on a surface area of the second base layer so as to be adjacent to both side walls of the trench provided with the first gate electrode and one side wall of the trench provided with the second gate electrode, respectively; an emitter layer of the second conductive type which is formed on the second surface; emitter electrodes which are formed on the second base layer and the source layers; a collector electrode which is formed on the emitter layer; and first and second terminals which are e

Abstract: A semiconductor device comprises a first base layer of a first conductivity type; a plurality of second base layers of a second conductivity type, provided on a part of a first surface of the first base layer; trenches formed on each side of the second base layers, and formed to be deeper than the second base layers; an emitter layer formed along the trench on a surface of the second base layers; a collector layer of the second conductivity type, provided on a second surface of the first base layer opposite to the first surface; an insulating film formed on an inner wall of the trench, the insulating film being thicker on a bottom of the trench than on a side surface of the trench; a gate electrode formed within the trench, and isolated from the second base layers and the emitter layer by the insulating film; and a space section provided between the second base layers adjacent to each other, the space section being deeper than the second base layers and being electrically isolated from the emitter layer and t

Abstract: This disclosure concerns a semiconductor device that includes a first base layer; second base layers provided on a part of a first surface of the first base layer; trenches formed on each side of the second base layers; an emitter layer formed on a surface of the second base layers; a collector layer provided below a second surface of the first base layer, an insulating film formed on an inner wall of the trench, the insulating film being thicker on a bottom of the trench than on a side surface of the trench; a gate electrode formed within the trench, and isolated by the insulating film; and a space section provided between the second base layers adjacent to each other, the space section being electrically isolated from the emitter layer and the second base layers, wherein the space section includes a semiconductor layer being deeper than the second base layers.

Abstract: 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.

Abstract: A semiconductor device includes a base layer of a first conductivity type, a barrier layer of a first conductivity type formed on the base layer, a trench formed from the surface of the barrier layer to such a depth as to reach a region in the vicinity of an interface between the barrier layer and the base layer, a gate electrode formed in the trench via a gate insulating film, a contact layer of a second conductivity type selectively formed in a surface portion of the barrier layer, a source layer of the first conductivity type selectively formed in the surface portion of the barrier layer so as to contact the contact layer and a side wall of the gate insulating film in the trench, and a first main electrode formed so as to contact the contact layer and the source layer.

Abstract: A semiconductor device includes a base layer of a first conductivity type, a barrier layer of a first conductivity type formed on the base layer, a trench formed from the surface of the barrier layer to such a depth as to reach a region in the vicinity of an interface between the barrier layer and the base layer, a gate electrode formed in the trench via a gate insulating film, a contact layer of a second conductivity type selectively formed in a surface portion of the barrier layer, a source layer of the first conductivity type selectively formed in the surface portion of the barrier layer so as to contact the contact layer and a side wall of the gate insulating film in the trench, and a first main electrode formed so as to contact the contact layer and the source layer.

Abstract: An object of the invention is to connect different dielectrics electrically to each other in the direction of main surface of a sheet in a multilayer ceramic substrate and to increase the degree of flexibility in design and make the multilayer ceramic substrate compact in size. A multilayer ceramic substrate in accordance with the invention is formed of a plurality of laminated ceramic substrates including such a composite ceramic substrate of different materials that is made by inserting the second ceramic substrate in a pounched-out portion made in the first ceramic substrate and by planarizing its top and bottom surfaces, wherein a conductive layer is formed in a portion across a boundary between the first ceramic substrate and the second ceramic substrate of the interface of the composite ceramic substrate of different materials.

Abstract: 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.

Abstract: An object of the invention is to connect different dielectrics electrically to each other in the direction of main surface of a sheet in a multilayer ceramic substrate and to increase the degree of flexibility in design and make the multilayer ceramic substrate compact in size. A multilayer ceramic substrate in accordance with the invention is formed of a plurality of laminated ceramic substrates including such a composite ceramic substrate of different materials that is made by inserting the second ceramic substrate in a pounched-out portion made in the first ceramic substrate and by planarizing its top and bottom surfaces, wherein a conductive layer is formed in a portion across a boundary between the first ceramic substrate and the second ceramic substrate of the interface of the composite ceramic substrate of different materials.

Abstract: An insulated gate semiconductor device, includes an isolating structure shaped in a circulating section along the periphery of a semiconductor substrate to isolate that part from an inside device region, a peripheral diffusion region of the semiconductor substrate located outside the isolating structure, a plurality of cell structures defined in the inside device region and divided in segments by insulated trench-shaped gates to have a base region covered with an emitter region in its upper surface, a collector region, and an emitter electrode electrically connected to the emitter region and the base region, a dummy base region contiguous to the cell structures and configured as a base region that has its upper surface left without the emitter region connected to the emitter electrode, an inner region defined in and insulated from the dummy base region, and a connection part to electrically connect the inner region to the emitter electrode.

Abstract: 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.

Abstract: A method for producing a multilayer ceramic substrate having a cavity formed therein includes punching a through opening corresponding to the cavity in green sheets constituting a laminate, and printing a conductor at a predetermined position of the green sheets, laminating the green sheets to constitute a green sheet laminate, and applying a pressure to the green sheet laminate by using a compression member having a projection at a position corresponding to the cavity to thereby compress the green sheet laminate. The projection has a height which is equal to the depth of the cavity multiplied by compression ratio of the green sheet laminate, and the green sheet laminate is compressed by applying the pressure such that compression ratio of the bottom of the cavity is identical with the compression ratio of other parts of the green sheet laminate.

Abstract: A semiconductor device including a base layer of a first conductivity type having a first main surface and a second main surface opposite the first main surface, a first main electrode layer connected to the first main surface, control regions arranged inside grooves penetrating the first main electrode layer and reach inside the base layer, and a second main electrode layer of the first conductivity type and connected to the second main surface.

Abstract: A power semiconductor device according to the present invention comprises: a first conductive type base layer; a second conductive type base layer selectively formed on the first conductive type base layer; an insulation layer formed in the region on the first conductive type base layer on which the second conductive type base layer is not formed; a gate insulation film formed on the inner surface of a trench formed between the second conductive type base layer and the insulation layer so as to separate them from each other and to reach the first conductive type base layer from the surface of the second conductive type base layer; a first conductive type source layer selectively formed on the surface of the second conductive type base layer in contact with the gate insulation film; a gate electrode formed in the trench and insulated from the first conductive type base layer, the second conductive type base layer, and the first conductive type source layer by the gate insulation film; a main electrode electric

Abstract: A semiconductor device disclosed herein comprises: a first base region which is of a first conductivity type; a second base region which is of a second conductivity type and which is selectively formed on a major surface of the first base region; a stopper region which is of a first conductivity type and which is formed on the major surface of the first base region, the stopper region being a predetermined distance away from the second base region and surrounding the second base region; and a ring region which is of a second conductivity type which is formed on the major surface of the first base region between the second base region and the stopper region, the ring region being spirally around the second base region and electrically connected to the second base region and the stopper region.

Abstract: A semiconductor device comprises a first base layer of a first conductive type which has a first surface and a second surface; a second base layer of a second conductive type which is formed on the first surface; first and second gate electrodes which are formed by embedding an electrically conductive material into a plurality of trenches via gate insulating films, the plurality of trenches being formed such that bottoms of the trenches reach the first base layer; source layers of the first conductive type which are formed on a surface area of the second base layer so as to be adjacent to both side walls of the trench provided with the first gate electrode and one side wall of the trench provided with the second gate electrode, respectively; an emitter layer of the second conductive type which is formed on the second surface; emitter electrodes which are formed on the second base layer and the source layers; a collector electrode which is formed on the emitter layer; and first and second terminals which are e

Abstract: 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.

Abstract: A semiconductor device comprises a first base layer of a first conductive type which has a first surface and a second surface; a second base layer of a second conductive type which is formed on the first surface; first and second gate electrodes which are formed by embedding an electrically conductive material into a plurality of trenches via gate insulating films, the plurality of trenches being formed such that bottoms of the trenches reach the first base layer; source layers of the first conductive type which are formed on a surface area of the second base layer so as to be adjacent to both side walls of the trench provided with the first gate electrode and one side wall of the trench provided with the second gate electrode, respectively; an emitter layer of the second conductive type which is formed on the second surface; emitter electrodes which are formed on the second base layer and the source layers; a collector electrode which is formed on the emitter layer; and first and second terminals which are e

Abstract: A plurality of first green sheets forming first ceramic layers after firing are stacked to form a first pre-fired substrate 4. Next, a plurality of second green sheets forming second ceramic layers after firing are stacked to form a second pre-fired substrate. Next, the first pre-fired substrate 4 is formed with recesses 10. Next, first pre-fired blocks 6 of sizes fitting into the recesses are formed from the second pre-fired substrate. The first pre-fired blocks 6 are fit into the recesses 10 so that the stacking direction A of the first green sheets and the stacking direction A? of the second green sheets become the same. The first pre-fired substrate 4 in which the first pre-fired blocks 6 are fit is fired.