Abstract: A semiconductor substrate of a semiconductor device includes a first conductive body region that is formed in the element region; a second conductive drift region that is formed in the element region; a gate electrode that is formed in the element region, that is arranged in a gate trench, and that faces the body region; an insulating body that is formed in the element region and is arranged between the gate electrode and an inside wall of the gate trench; a first conductive floating region that is formed in the element region and that is surrounded by the drift region; a first voltage-resistance retaining structure that is formed in the peripheral region and that surrounds the element region; and a gate pad that is formed in the peripheral region, and is electrically connected to the gate electrode in a position on the element region-side of the first voltage-resistance retaining structure.

Abstract: A SiC semiconductor device includes: a semiconductor switching element having: a substrate, a drift layer and a base region stacked in this order; a source region and a contact region in the base region; a trench extending from a surface of the source region to penetrate the base region; a gate electrode on a gate insulating film in the trench; a source electrode electrically coupled with the source region and the base region; a drain electrode on a back side of the substrate; and multiple deep layers in an upper portion of the drift layer deeper than the trench. Each deep layer has upper and lower portions. A width of the upper portion is smaller than the lower portion.

Abstract: A semiconductor device has a stacked structure in which a p-GaN layer, an SI-GaN layer, and an AlGaN layer are stacked, and has a gate electrode that is formed at a top surface side of the AlGaN layer. A band gap of the AlGaN layer is wider than a band gap of the p-GaN layer and the SI-GaN layer. Moreover, impurity concentration of the SI-GaN layer is less than 1×1017 cm?3. Semiconductor devices including III-V semiconductors may have a stable normally-off operation.

Abstract: A method for producing a semiconductor device includes: an arranging process of arranging a plurality of silicon carbide wafers having opposed first and surfaces so that the first surface and the second surface of adjacent silicon carbide wafers face each other and are separated in parallel; and a heat treatment process of heating the arranged plurality of silicon carbide wafers so that the first surface of each silicon carbide wafer becomes higher in temperature than the second surface thereof, and, in the adjacent silicon carbide wafers, the second surface of one silicon carbide wafer becomes higher in temperature than the first surface of the other silicon carbide wafer that faces the second surface.

Abstract: A wafer examination device includes a probe, a fusion section and a measurement section. The probe is made of a metal which reacts with silicon carbide to produce silicide. The fusion section fuses the probe to a silicon carbide wafer as an examined object. The measurement section measures an electrical property of the silicon carbide wafer through the fused probe.

Abstract: A switching element is provided having a semiconductor substrate. A trench gate electrode is formed in the upper surface of the semiconductor substrate. An n-type first semiconductor region, a p-type second semiconductor region, and an n-type third semiconductor region are formed in a region in contact with a gate insulating film in the semiconductor substrate. At a position below the second semiconductor region, there is formed a p-type fourth semiconductor region connected to the second semiconductor region and opposing the gate insulating film via the third semiconductor region and containing boron. A high-concentration-carbon containing region having a carbon concentration higher than that of a semiconductor region exposed on the lower surface of the semiconductor substrate is formed in at least a part of the portion of the third semiconductor region, positioned between the fourth semiconductor region and the gate insulating film, that is in contact with the fourth semiconductor region.

Abstract: A SiC semiconductor device includes: a substrate, a drift layer, and a base region stacked in this order; first and second source regions and a contact layer in the base region; a trench penetrating the source and base regions; a gate electrode in the trench; an interlayer insulation film with a contact hole covering the gate electrode; a source electrode coupling with the source region and the contact layer via the contact hole; a drain electrode on the substrate; and a metal silicide film. The high concentration second source region is shallower than the low concentration first source region, and has a part covered with the interlayer insulation film, which includes a low concentration first portion near a surface and a high concentration second portion deeper than the first portion. The metal silicide film on the second part has a thickness larger than the first portion.

Abstract: A semiconductor substrate of a semiconductor device includes a body region of a first conductivity type, a drift region of a second conductivity type coming into contact with a lower surface of the body region, a gate electrode that is provided in a gate trench passing through the body region and extending to the drift region and faces the body region, and a gate insulator that is provided between the gate electrode and a wall surface of the gate trench. An inverted U-shaped section is formed in a lower surface of the gate insulator, and a floating region of the first conductivity type is formed in the inverted U-shaped section. The floating region protrudes under a portion that is located at a lowermost portion in the lower surface of the gate insulator.

Abstract: The silicon carbide semiconductor device includes a substrate, a drift layer, a base region, a source region, a trench, a gate insulating layer, a gate electrode, a source electrode, a drain electrode, and a deep layer. The deep layer is disposed under the base region and is located to a depth deeper than the trench. The deep layer is divided into a plurality of portions in a direction that crosses a longitudinal direction of the trench. The portions include a group of portions disposed at positions corresponding to the trench and arranged at equal intervals in the longitudinal direction of the trench. The group of portions surrounds corners of a bottom of the trench.

Abstract: A manufacturing method of a silicon carbide semiconductor device includes: forming a drift layer on a silicon carbide substrate; forming a base layer on or in a surface portion of the drift layer; forming a source region in a surface portion of the base layer; forming a trench to penetrate the base layer and to reach the drift layer; forming a gate electrode on a gate insulation film in the trench; forming a source electrode electrically connected to the source region and the base layer; and forming a drain electrode on a back surface of the substrate. The forming of the trench includes: flattening a substrate surface; and etching to form the trench after flattening.

Abstract: An SiC semiconductor device includes a substrate, a drift layer, a base region, a source region, a trench, a gate oxide film, a gate electrode, a source electrode and a drain electrode. The substrate has a Si-face as a main surface. The source region has the Si-face. The trench is provided from a surface of the source region to a portion deeper than the base region and extends longitudinally in one direction and has a Si-face bottom. The trench has an inverse tapered shape, which has a smaller width at an entrance portion than at a bottom, at least at a portion that is in contact with the base region.

Abstract: A SiC semiconductor device includes: a SiC substrate including a first or second conductive type layer and a first conductive type drift layer and including a principal surface having an offset direction; a trench disposed on the drift layer and having a longitudinal direction; and a gate electrode disposed in the trench via a gate insulation film. A sidewall of the trench provides a channel formation surface. The vertical semiconductor device flows current along with the channel formation surface of the trench according to a gate voltage applied to the gate electrode. The offset direction of the SiC substrate is perpendicular to the longitudinal direction of the trench.

Abstract: A manufacturing method of an SiC single crystal includes preparing an SiC substrate, implanting ions into a surface portion of the SiC substrate to form an ion implantation layer, activating the ions implanted into the surface portion of the SiC substrate by annealing, chemically etching the surface portion of the SiC substrate to form an etch pit that is caused by a threading screw dislocation included in the SiC substrate and performing an epitaxial growth of SiC to form an SiC growth layer on a surface of the SiC substrate including an inner wall of the etch pit in such a manner that portions of the SiC growth layer grown on the inner wall of the etch pit join with each other.

Abstract: A semiconductor device includes a semiconductor substrate and an electric field terminal part. The semiconductor substrate includes a substrate, a drift layer disposed on a surface of the substrate, and a base layer disposed on a surface of the drift layer. The semiconductor substrate is divided into a cell region in which a semiconductor element is disposed and a peripheral region that surrounds the cell region. The base region has a bottom face located on a same plane throughout the cell region and the peripheral region and provides an electric field relaxing layer located in the peripheral region. The electric field terminal part surrounds the cell region and a portion of the electric field relaxing layer and penetrates the electric field relaxing layer from a surface of the electric field relaxing layer to the drift layer.

Abstract: A switching element is provided having a semiconductor substrate. A trench gate electrode is formed in the upper surface of the semiconductor substrate. An n-type first semiconductor region, a p-type second semiconductor region, and an n-type third semiconductor region are formed in a region in contact with a gate insulating film in the semiconductor substrate. At a position below the second semiconductor region, there is formed a p-type fourth semiconductor region connected to the second semiconductor region and opposing the gate insulating film via the third semiconductor region and containing boron. A high-concentration-carbon containing region having a carbon concentration higher than that of a semiconductor region exposed on the lower surface of the semiconductor substrate is formed in at least a part of the portion of the third semiconductor region, positioned between the fourth semiconductor region and the gate insulating film, that is in contact with the fourth semiconductor region.

Abstract: A method for manufacturing a semiconductor device including a semiconductor substrate composed of silicon carbide, an upper surface electrode which contacts an upper surface of the substrate, and a lower surface electrode which contacts a lower surface of the substrate, the method including steps of: (a) forming an upper surface structure on the upper surface side of the substrate, and (b) forming a lower surface structure on the lower surface side of the substrate. The step (a) comprises steps of: (a1) depositing an upper surface electrode material layer on the upper surface of the substrate, the upper surface electrode material layer being a raw material layer of the upper surface electrode, and (a2) annealing the upper surface electrode material layer.

Abstract: A method for manufacturing a switching device, which includes a trench type gate electrode and first to fourth semiconductor regions, is provided. The first semiconductor region is in contact with a gate insulating film and is of n-type. The second semiconductor region is in contact with the gate insulating film, and is of p-type. The third semiconductor region is in contact with the gate insulating film, and is of n-type. The fourth semiconductor region is a p-type semiconductor region which is positioned in a range deeper than the second semiconductor region and consecutive with the second semiconductor region, and which faces the gate insulating film via the third semiconductor region. The manufacturing method includes forming the second semiconductor region in which aluminum is doped, and implanting boron into a range in which the fourth semiconductor region is to be formed in the semiconductor substrate.

Abstract: In a silicon carbide semiconductor device, a plurality of trenches has a longitudinal direction in one direction and is arranged in a stripe pattern. Each of the trenches has first and second sidewalls extending in the longitudinal direction. The first sidewall is at a first acute angle to one of a (11-20) plane and a (1-100) plane, the second sidewall is at a second acute angle to the one of the (11-20) plane and the (1-100) plane, and the first acute angle is smaller than the second acute angle. A first conductivity type region is in contact with only the first sidewall in the first and second sidewalls of each of the trenches, and a current path is formed on only the first sidewall in the first and second sidewalls.

Abstract: A SiC device includes an inversion type MOSFET having: a substrate, a drift layer, and a base region stacked in this order; source and contact regions in upper portions of the base region; a trench penetrating the source and base regions; a gate electrode on a gate insulating film in the trench; a source electrode coupled with the source and base region; a drain electrode on a back of the substrate; and multiple deep layers in an upper portion of the drift layer deeper than the trench. Each deep layer has an impurity concentration distribution in a depth direction, and an inversion layer is provided in a portion of the deep layer on the side of the trench under application of the gate voltage.

Abstract: A SiC semiconductor device includes: a SiC substrate including a first or second conductive type layer and a first conductive type drift layer and including a principal surface having an offset direction; a trench disposed on the drift layer and having a longitudinal direction; and a gate electrode disposed in the trench via a gate insulation film. A sidewall of the trench provides a channel formation surface. The vertical semiconductor device flows current along with the channel formation surface of the trench according to a gate voltage applied to the gate electrode. The offset direction of the SiC substrate is perpendicular to the longitudinal direction of the trench.