This invention discloses a semiconductor device disposed in a semiconductor substrate. The semiconductor device includes a first semiconductor layer of a first conductivity type on a first major surface. The semiconductor device further includes a second semiconductor layer of a second conductivity type on a second major surface opposite the first major surface. The semiconductor device further includes an injection efficiency controlling buffer layer of a first conductivity type disposed immediately below the second semiconductor layer to control the injection efficiency of the second semiconductor layer.

A semiconductor device includes a first conductivity type semiconductor substrate, a second conductivity type first and second buried diffusion layers that are arranged in the semiconductor substrate, a semiconductor layer arranged on the semiconductor substrate, a second conductivity type first impurity diffusion region that is arranged in the semiconductor layer, a second conductivity type second impurity diffusion region that is arranged, in the semiconductor layer, on the second buried diffusion layer, a second conductivity type first well that is arranged in a first region of the semiconductor layer, a first conductivity type second well that is arranged, in the semiconductor layer, in a second region, a first conductivity type third and fourth impurity diffusion regions that are arranged in the first well, and a first conductivity type fifth impurity diffusion region that is arranged in the second well.

An IGBT includes an n-type drift layer, a p-type base layer and an n-type emitter layer formed on an upper surface of the n-type drift layer, and a p-type collector layer on a lower surface of the n-type drift layer. A FWD includes the n-type drift layer, a p-type anode layer formed on the upper surface of the n-type drift layer and an n-type cathode layer formed on the lower surface of the n-type drift layer. A p-type well is formed on the upper surface of the n-type drift layer in a wiring region and a termination region. A wiring is formed on the p-type well in the wiring region. The p-type well has a higher impurity concentration and is deeper than the p-type anode layer. The p-type well is not formed directly above the n-type cathode layer and is separate from a region directly above the n-type cathode layer.

A semiconductor device is provide that includes: a semiconductor body having a first surface, an inner region, and an edge region; a pn junction between a first semiconductor region of a first conductivity type and a second semiconductor region of a second conductivity type, the pn-junction extending in a lateral direction of the semiconductor body in the inner region; a recess extending from the first surface in the edge region into the semiconductor body, the recess comprising at least one sidewall; a dielectric filling the recess. In the dielectric, a dielectric number, in the lateral direction, decreases as a distance from the first sidewall increases.

A semiconductor device according to the embodiments includes a SiC layer having a first plane, an insulating layer, and a region between the first plane and the insulating layer, the region including at least one element in the group consisting of Be (beryllium), Mg (magnesium), Ca (calcium), Sr (strontium), and Ba (barium), a full width at half maximum of a concentration peak of the element being equal to or less than 1 nm, and when a first area density being an area density of Si (silicon) and C (carbon) including a bond which does not bond with any of Si and C in the SiC layer at the first plane and a second area density being an area density of the element, the second area density being equal to or less than of the first area density.

A silicon carbide semiconductor device includes an impurity region including a p type impurity and disposed within a silicon carbide layer to surround an element region as seen in plan view. The impurity region has a peak concentration of the p type impurity at a position within the silicon carbide layer distant from a first main surface. The peak concentration is not less than 110.sup.16 cm.sup.3 and not more than 510.sup.17 cm.sup.3. The impurity region is formed by implanting ions of the p type impurity into the silicon carbide layer. Then, a silicon dioxide film is formed to cover the first main surface of the silicon carbide layer by performing a thermal oxidation process on the silicon carbide layer, and the concentration of the p type impurity in the vicinity of the first main surface is lowered.

A semiconductor device includes: a semiconductor substrate; a device region on the semiconductor substrate; a planar edge termination region on the semiconductor substrate to surround the device region; and a passivation film covering the edge termination region, wherein the passivation film includes a semi-insulating film directly contacting the semiconductor substrate.

Reduction of power consumption of a semiconductor device is aimed. The semiconductor device includes a cell region where a vertical power MOSFET is formed and an intermediate region surrounding the cell region. In each of the cell region and the intermediate region, a plurality of p-type column regions and a plurality of n-type column regions are alternately formed. The n-type column region arranged in the cell region has a defect region formed therein, whereas the n-type column region arranged in the intermediate region does not have the defect region. A defect density in the n-type column region arranged in the cell region is larger than that in the n-type column region arranged in the intermediate region.

A semiconductor device capable of carrying out temperature detection appropriately by a temperature sensor is provided. In a semiconductor device disclosed herein, a first width of a first portion within a front surface insulating film (that is, part located in an upper part of an active region among a part extending along a first side of a front surface electrode that is closer to the temperature sensor) is wider than a second width of a second portion within the front surface insulating film (that is, part located in the upper part of the active region among a part extending along a second side of the front surface electrode).

A power semiconductor is disclosed and for high-voltage and high-power operation. An example power semiconductor comprises: a substrate; a drift layer formed in the substrate including an active area having doped regions and a termination area configured to surround the active area; and a junction termination extension (JTE) in the termination area. In some aspects, the substrate and the drift layer comprise a first conductivity type, the doped regions and the JTE comprise a second conductivity type, the JTE comprises at least one blocking region adjacent to an edge of the active area and a plurality of separation regions, each separation region of the plurality of separation regions comprises two or more separation sub-regions, and the two or more separation sub-regions are configured to have a different dopant concentrations