A semiconductor device includes a substrate having opposed first and second major surface, an active area, and a termination area. Insulated trenches extend from the first major surface toward the second major surface, each of the insulated trenches including a conductive field plate and a gate electrode overlying the conductive field plate, the gate electrode being separated from the field plate by a gate-field plate insulator. The field plate extends longitudinally in both of the active and termination areas and the gate electrode is absent in the termination area. A body region of a first conductivity type extends laterally between pairs of the insulated trenches. First and second spacer regions of a second conductivity type extend laterally between the pairs of the insulated trenches at the termination area to produce segments of the first conductivity type between the first and second spacer regions that are isolated from the body region.

According to one embodiment, a wafer includes a substrate and a crystal layer. The substrate includes a plurality of SiC regions including SiC and an inter-SiC region including Si provided between the SiC regions. The crystal layer includes a first layer, and a first intermediate layer provided between the substrate and the first layer in a first direction. The first layer includes SiC and nitrogen. The first intermediate layer includes SiC and nitrogen. A second concentration of nitrogen in the first intermediate layer is higher than a first concentration of nitrogen in the first layer.

A semiconductor device has a cell region formed with a semiconductor element and an outer peripheral region surrounding the cell region. The outer peripheral region includes a guard ring part having a plurality of guard rings of the second conductivity-type, and a plurality of guard ring column regions of the second conductivity-type. Each of the guard rings is disposed in a surface layer portion of the drift layer and has a frame shape surrounding the cell region. The guard ring column regions are extended from the guard rings toward the substrate. Each of the guard ring column regions has a width smaller than a width of each of the guard rings in a direction along a planar direction of the substrate in a predetermined cross-section defined along the cell region and the outer peripheral region. At least two guard ring column regions are provided for each guard ring.

The semiconductor device of the present invention includes a first conductivity type semiconductor layer made of a wide bandgap semiconductor and a Schottky electrode formed to come into contact with a surface of the semiconductor layer, and has a threshold voltage V.sub.th of 0.3 V to 0.7 V and a leakage current J.sub.r of 1×10.sup.−9 A/cm.sup.2 to 1×10.sup.−4 A/cm.sup.2 in a rated voltage V.sub.R.

In an intermediate region surrounding a periphery of an active region, a gate polysilicon wiring layer is provided on a gate insulating film at a front surface of a semiconductor substrate, via a field oxide film. An inner end portion of the gate polysilicon wiring layer faces a p-type region of a surface region at the front surface of the semiconductor substrate, via only the gate insulating film. In the intermediate region, at corners thereof facing corners of the active region, a low carrier lifetime region containing a carrier lifetime killer is provided so as to overlap the p-regions and, in a depth direction, face the gate polysilicon wiring layer, whereby the lifetime of the minority carriers of the corner portions of the intermediate region is shorter than the lifetime of the minority carriers of linear portions of the intermediate region.

A semiconductor device is described. The semiconductor device includes: a semiconductor substrate having an edge, an active area spaced inward from the edge, and an edge termination area laterally surrounding the active area; and a plurality of transistor cells formed in the active area, each transistor cell including a source region of a first conductivity type and a body region of a second conductivity type opposite the first conductivity type. The edge termination area includes a plurality of needle-shaped compensation trenches and is devoid of complete transistor cells. A body doping region of the second conductivity type and that includes the body regions of the transistor cells extends from the active area into the edge termination area. The body doping region in the edge termination area is physically and electrically isolated from the body doping region in the active area.

A base layer has a low concentration peak at a position between a portion located at a same depth as a lower end portion of a gate electrode and a portion located at a same depth as an upper end portion of the gate electrode in a concentration profile of an impurity concentration in a depth direction. An impurity region has a boundary with the base layer in the depth direction at a position between a first peak position, at which the impurity concentration of the base layer is maximum between the portion located at the same depth as the lower end portion and the position of the low concentration peak, and a second peak position, at which the impurity concentration of the base layer is maximum between the position of the low concentration peak and the portion located at the same depth as the upper end portion.

A semiconductor device and a method of manufacturing the same capable of ensuring a sufficient breakdown voltage near a terminal end portion of a cell portion are provided. The cell portion includes a first cell column region and a second cell column region adjacent to each other, and a first cell trench gate and a second cell trench gate arranged between the first cell column region and the second cell column region. An outer peripheral portion includes an outer peripheral trench gate connected to an end portion of each of the first cell trench gate and the second cell trench gate, and a first outer peripheral column region arranged on the cell portion side with respect to the outer peripheral trench gate and extended across the first cell trench gate and the second cell trench gate in plan view.

A semiconductor device has an active region through which current passes and an edge termination structure region. On a front surface of a semiconductor substrate of a first conductivity type, a first semiconductor layer of the first conductivity type is provided. On a surface of the first semiconductor layer, a parallel pn structure including first columns of the first conductivity type and second columns of a second conductivity type disposed to repeatedly alternate one another is provided. The second columns in the active region include first regions and second regions. A distance from the front surface of the semiconductor substrate to a bottom surface of one of the first regions is greater than a distance from the front surface of the semiconductor substrate to a bottom surface of one of the second regions.

A semiconductor device includes a semiconductor substrate in which a first region having a freewheeling diode arranged therein, second regions having an IGBT arranged therein, and a withstand-voltage retention region surrounding the first region and the second regions in plan view are defined. The semiconductor substrate has a first main surface and a second main surface. The semiconductor substrate includes an anode layer having a first conductivity type, which is arranged in the first main surface of the first region, and a diffusion layer having the first conductivity type, which is arranged in the first main surface of the withstand-voltage retention region adjacently to the anode layer. A first trench is arranged in the first main surface on a side of the anode layer with respect to a boundary between the anode layer and the diffusion layer.