Patent application number | Description | Published |
20110012133 | SILICON CARBIDE SEMICONDUCTOR DEVICE AND METHOD FOR MANUFACTURING THE SAME - A silicon carbide MOSFET that exhibits a high source-to-drain withstand voltage and that involves a smaller difference between gate-to-drain capacitance achieved in an activated state and gate-to-drain capacitance achieved in a deactivated state. A silicon carbide drift layer of a first conductivity type is provided on a silicon carbide substrate of a first conductivity type; a pair of base regions are provided in a surface layer portion of the silicon carbide drift layer and exhibit a second conductivity type; a pair of source regions are provided in interiors of surface layer portions of the pair of base regions and exhibit a first conductivity type; and semi-insulating regions are provided between the silicon carbide substrate and the pair of base regions. | 01-20-2011 |
20110062491 | POWER SEMICONDUCTOR MODULE - A power semiconductor module ( | 03-17-2011 |
20110210392 | POWER SEMICONDUCTOR DEVICE - A structure of a power semiconductor device, in which a P-well region having a large area and a gate electrode are opposed to each other through a field oxide film having a larger thickness than that of a gate insulating film such that the P-well region having a large area and the gate electrode are not opposed to each other through the gate insulating film, or the gate electrode is not provided above the gate insulating film that includes the P-well region having a large area therebelow. | 09-01-2011 |
20110278599 | SILICON CARBIDE SEMICONDUCTOR DEVICE - A SiC semiconductor device capable of increasing a switching speed without destroying a gate insulating film. In addition, in a SiC-MOSFET including an n-type semiconductor substrate formed of SiC, a p-type semiconductor layer is entirely or partially provided on an upper surface of a p-type well layer that has a largest area of the transverse plane among a plurality of p-type well layers provided in an n-type drift layer and is arranged on an outermost periphery immediately below a gate electrode pad. It is preferable that a concentration of an impurity contained in the p-type semiconductor layer be larger than that of the p-type well layer. | 11-17-2011 |
20110284874 | SEMICONDUCTOR DEVICE AND METHOD FOR MANUFACTURING THE SAME - In a cell region of a first major surface of a semiconductor substrate of a first conductivity type, a first well of a second conductivity type is in an upper surface. A diffusion region of a first conductivity type is in the upper surface in the first well. A first gate insulating film is on the first well, and a first gate electrode on the first gate insulating film. A second well of a second conductivity type is in the upper surface of the first major surface on a peripheral portion of the cell region. A second gate insulating film is on the second well, and a thick field oxide film is on the peripheral side than the second gate insulating film. A second gate electrode is sequentially on the second gate insulating film and the field oxide film and electrically connected to the first gate electrode. A first electrode is connected to the first, second well and the diffusion region. A second electrode is connected on a second major surface of the semiconductor substrate. A gate wiring is on the field oxide film, going around a periphery of the cell region, and electrically connected to the second gate electrode. The gate wiring is a silicide of a constituting substance of the second gate electrode. | 11-24-2011 |
20120061688 | POWER SEMICONDUCTOR DEVICE AND METHOD FOR MANUFACTURING THE POWER SEMICONDUCTOR DEVICE - In a power semiconductor device that switches at a high speed, a displacement current flows at a time of switching, so that a high voltage occurs which may cause breakdown of a thin insulating film such as a gate insulating film. A semiconductor device includes: a semiconductor substrate of a first conductivity type; a drift layer of the first conductivity type formed on a first main surface of the semiconductor substrate; a first well region of a second conductivity type formed in a part of a surface layer of the drift layer; a second well region of the second conductivity type formed in a part of the surface layer of the drift layer at a distance from the first well region, the second well region having a smaller area than that of the first well region when seen above an upper surface thereof; a low-resistance region of the first conductivity type formed in a surface layer of the first well region, the low-resistance region having a higher impurity concentration than that of the first well region; a gate insulating film formed on and in contact with a surface of the first well region; and a gate electrode formed on and in contact with a surface of the gate insulating film. | 03-15-2012 |
20120205669 | POWER SEMICONDUCTOR DEVICE - In a semiconductor device according to the present invention, a p-type well region disposed in an outer peripheral portion of the power semiconductor device is divided into two parts, that is, an inside and an outside, and a field oxide film having a greater film thickness than the gate insulating film is provided on a well region at the outside to an inside of an inner periphery of the well region. Therefore, it is possible to prevent, in the gate insulating film, a dielectric breakdown due to the voltage generated by the flow of the displacement current in switching. | 08-16-2012 |
20130020586 | SEMICONDUCTOR DEVICE - A semiconductor device having a low feedback capacitance and a low switching loss. The semiconductor device includes: a substrate; a drift layer formed on a surface of the semiconductor substrate; a plurality of first well regions formed on a surface of the drift layer; a source region which is an area formed on a surface of each of the first well regions and defining, as a channel region, the surface of each of the first well regions interposed between the area and the drift layer; a gate electrode formed over the channel region and the drift layer thereacross through a gate insulating film; and second well regions buried inside the drift layer below the gate electrode and formed to be individually connected to each of the first well regions adjacent to one another. | 01-24-2013 |
20130020587 | POWER SEMICONDUCTOR DEVICE AND METHOD FOR MANUFACTURING SAME - A semiconductor device includes a semiconductor substrate of a first conductivity type, a drift layer of the first conductivity type which is formed on a first main surface of the semiconductor substrate, a second well region of a second conductivity type which is formed to surround a cell region of the drift layer, and a source pad for electrically connecting the second well regions and a source region of the cell region through a first well contact hole provided to penetrate a gate insulating film on the second well region, a second well contact hole provided to penetrate a field insulating film on the second well region and a source contact hole. | 01-24-2013 |
20130288467 | METHOD OF MANUFACTURING SEMICONDUCTOR DEVICE - A semiconductor device capable of suppressing generation of a high electric field and preventing a dielectric breakdown from occurring, and a method of manufacturing the same. The method of manufacturing a semiconductor device includes (a) preparing an n+ substrate to be a ground constituted by a silicon carbide semiconductor of a first conductivity type, (b) forming a recess structure surrounding an element region on the n+ substrate by using a resist pattern, and (c) forming a guard ring injection layer to be an impurity layer of a second conductivity type in a recess bottom surface and a recess side surface in the recess structure by impurity injection through the resist pattern, and a corner portion of the recess structure is covered with the impurity layer. | 10-31-2013 |
20140203393 | SEMICONDUCTOR DEVICE - A semiconductor device having high breakdown voltage and high reliability without forming an embedded injection layer with high position accuracy. The semiconductor device includes a base as an active area of a second conductivity type formed on a surface layer of a semiconductor layer of a first conductivity type to constitute a semiconductor element; guard rings as a plurality of first impurity regions of the second conductivity type formed on the surface layer of the semiconductor layer spaced apart from each other to respectively surround the base in plan view; and an embedded injection layer as a second impurity region of the second conductivity type embedded in the surface layer of the semiconductor layer to connect at least two bottom portions of the plurality of guard rings. | 07-24-2014 |
20140299888 | SILICON CARBIDE SEMICONDUCTOR DEVICE - A SiC semiconductor device capable of increasing a switching speed without destroying a gate insulating film. In addition, in a SiC-MOSFET including an n-type semiconductor substrate formed of SiC, a p-type semiconductor layer is entirely or partially provided on an upper surface of a p-type well layer that has a largest area of the transverse plane among a plurality of p-type well layers provided in an n-type drift layer and is arranged on an outermost periphery immediately below a gate electrode pad. It is preferable that a concentration of an impurity contained in the p-type semiconductor layer be larger than that of the p-type well layer. | 10-09-2014 |
20140353686 | SEMICONDUCTOR DEVICE - A semiconductor device having a low feedback capacitance and a low switching loss. The semiconductor device includes: a substrate; a drift layer formed on a surface of the semiconductor substrate; a plurality of first well regions formed on a surface of the drift layer; a source region which is an area formed on a surface of each of the first well regions and defining, as a channel region, the surface of each of the first well regions interposed between the area and the drift layer; a gate electrode formed over the channel region and the drift layer thereacross through a gate insulating film; and second well regions buried inside the drift layer below the gate electrode and formed to be individually connected to each of the first well regions adjacent to one another. | 12-04-2014 |