A semiconductor device, including a substrate, a deposition layer deposited on the substrate, a semiconductor region selectively provided in the deposition layer, a semiconductor layer provided on the deposition layer and the semiconductor region, a first region and a second region selectively provided in the semiconductor layer, a gate electrode provided on the second region and the semiconductor layer via a gate insulating film, a source electrode in contact with the semiconductor layer and the second region, an interlayer insulating film covering the gate electrode, a drain electrode provided on the substrate, a plating film selectively provided on the source electrode at portions thereof on which the protective film is not provided, and a pin-shaped electrode connected to the plating film via solder. The second region is not formed directly beneath a portion where the plating film, the protective film and the source electrode are in contact with one another.

A semiconductor device of the present invention includes a semiconductor layer, a gate trench that defines a source region of a first conductivity type in the semiconductor layer, a channel region of a second conductivity type of a lower part of the source region, a source trench that passes through the source region and the channel region, an impurity region of the second conductivity type of a bottom part and a side part of the source trench, a source electrode on the semiconductor layer, and a highly-concentrated impurity region of the second conductivity type, the highly-concentrated impurity region having a contact portion connected to the source electrode at a surface of the semiconductor layer, the highly-concentrated impurity region passing through the source region and extending to a position deeper than the source region, the highly-concentrated impurity region having a concentration higher than the impurity region.

A silicon carbide semiconductor device has a silicon carbide substrate and an insulating film. The silicon carbide substrate includes a termination region having a peripheral edge, and an element region surrounded by the termination region. The insulating film is provided on the termination region. The termination region includes a first impurity region having a first conductivity type, and a field stop region having the first conductivity type, being in contact with the first impurity region and having a higher impurity concentration than the first impurity region. The field stop region is at least partially exposed at the peripheral edge.

A semiconductor device includes: an n− type layer disposed on a first surface of an n+ type silicon carbide substrate; a first trench and a second trench formed in the n− type layer and separated from each other; an n+ type region disposed between a side surface of the first trench and the side surface of the second trench and disposed on the n− type layer; a gate insulating layer disposed inside the first trench; a source insulating layer disposed inside the second trench; a gate electrode disposed on the gate insulating layer; an oxide layer disposed on the gate electrode; a source electrode disposed on the oxide layer, the n+ type region, and the source insulating layer; and a drain electrode disposed on a second surface of the n+ type silicon carbide substrate.

According to one embodiment, a semiconductor device includes first to fourth semiconductor regions, first and second electrodes, and a first insulating film. The first semiconductor region includes first and second partial regions, and an intermediate partial region. The first electrode is separated from the first partial region. The second electrode includes first and second conductive regions. The second semiconductor region is provided between the first conductive region and the first electrode. The third semiconductor region is provided between the first conductive region and at least a portion of the second semiconductor region. The fourth semiconductor region includes third and fourth partial regions. The fourth partial region is positioned between the first conductive region and the first electrode. The first insulating film is provided, between the fourth partial region and the first electrode, and between the second semiconductor region and the first electrode.

A method for forming a semiconductor device includes: forming a trench structure with trenches in an inner region and an edge region of a SiC semiconductor body such that the trench structure extends from a first surface of the semiconductor body through a second semiconductor layer into a first semiconductor layer and such that the trench structure, in the second semiconductor layer, forms mesa regions; and forming at least one transistor cell at least partially in each of the mesa regions in the inner region. Forming each transistor cell includes forming at least one compensation region. Forming the compensation region includes implanting dopant atoms of a second doping type via sidewalls of the trenches into the mesa regions in the inner region. Forming the compensation region in each mesa region in the inner region includes at least partially covering the edge region with an implantation mask.

The present disclosure has an object of providing a silicon carbide semiconductor device with high productivity which prevents characteristic degradation occurring when a large current is applied to a body diode. A structure including a SiC substrate, a buffer layer, and a drift layer is classified into an active region through which a current flows with application of a voltage to the SiC-MOSFET, and a breakdown voltage support region around a periphery of the active region in a plan view. The active region is classified into a first active region in a center portion, and a second active region between the first active region and the breakdown voltage support region in the plan view. Lifetimes of minority carriers in the second active region and the breakdown voltage support region are shorter than that in the first active region.

A cell structure of a silicon carbide MOSFET device, comprising a drift region (3) located on a substrate layer (2), a second conducting type well region (4) and a first JFET region (51) that are located in the drift region (3), an enhancement region located within a surface of the well region (4), a gate insulating layer (8) located on a first conducting type enhancement region (6), the well region (4) and the first JFET region (51) and being in contact therewith at the same time, a gate (9) located on the gate insulating layer, source metal (10) located on the enhancement region, Schottky metal (11) located on a second conducting type enhancement region (7) and the drift region (3), a second JFET region (52) located on a surface of the drift region (3) between the Schottky metals (11), and drain metal (12).

Semiconductor device including first semiconductor layer of a first conductivity type, second semiconductor layer of a second conductivity type at a surface of the first semiconductor layer, third semiconductor layer of the first conductivity type selectively provided at a surface of the second layer, and gate electrode embedded in a trench via a gate insulating film. The trench penetrates the second and third layers, and reaches the first layer. A thermal oxide film on the third layer has a thickness less than that of the gate insulating film. Also are an interlayer insulating film on the thermal oxide film, barrier metal on an inner surface of a contact hole selectively opened in the thermal oxide film and the interlayer insulating film, metal plug embedded in the contact hole on the barrier metal, and electrode electrically connected to the second and third layers via the barrier metal and the metal plug.

First p.sup.+-type regions are provided directly beneath trenches, separate from a p-type base region and facing bottoms of the trenches in a depth direction. The first p.sup.+-type regions are exposed at the bottoms of the trenches and are in contact with a gate insulating film at the bottoms of the trenches. Second p.sup.+-type regions are each provided between (mesa region) adjacent trenches, separate from the first p.sup.+-type regions and the trenches. Drain-side edges of the second p.sup.+-type regions are positioned closer to a source side than are drain-side edges of the first p.sup.+-type regions. In each mesa region, an n.sup.+-type region is provided separate from the first p.sup.+-type regions and the trenches. The n.sup.+-type regions are adjacent to and face the second p.sup.+-type regions in the depth direction.