Abstract: A trench gate MOSFET has at an n-type current spreading region between an n?-type drift region and a p-type base region, a first p+-type region facing a bottom of a trench, and a second p+-type region disposed between adjacent trenches. The first and the second p+-type regions extend parallel to a first direction in which the trench extends and are partially connected by a p+-type connecting portion and thus, disposed in a ladder shape when viewed from the front surface of a semiconductor substrate. The second p+-type region has at a portion of a surface on a drain side, a recessed portion that is recessed toward a source side. One or more recessed portions is provided between connection sites in the second p+-type region for connection with the p+-type connecting portions that are adjacent to each other in the first direction X.

Abstract: A semiconductor device includes an active region through which a main current passes during an ON state. In the active region, the semiconductor device includes a semiconductor substrate of a first conductivity type, a first semiconductor layer of the first conductivity type, a second semiconductor layer of a second conductivity type, first semiconductor regions of the first conductivity type, gate insulating films, gate electrodes, an interlayer insulating film, first electrodes, a second electrode, first trenches, a second trench, a polycrystalline silicon layer provided in the second trench via one of the gate insulating films, and a silicide layer selectively provided in a surface layer of the polycrystalline silicon layer. The polycrystalline silicon layer and the silicide layer are electrically connected with the gate electrodes.

Abstract: A semiconductor device includes a semiconductor substrate of a first conductivity type, a first semiconductor layer of the first conductivity type, a second semiconductor layer of a second conductivity type, first semiconductor regions of the first conductivity type, second semiconductor regions of the second conductivity type, gate insulating films, gate electrodes, an insulating film, first electrodes, a second electrode, and trenches. The first semiconductor regions and the second semiconductor regions are periodically disposed apart from one another in a first direction in which the trenches extend in a stripe pattern.

Abstract: A semiconductor device, including a semiconductor substrate of a first conductivity type, a first semiconductor layer of the first conductivity type, provided on the semiconductor substrate and having an impurity concentration lower than that of the semiconductor substrate, a second semiconductor layer of a second conductivity type, selectively provided on the first semiconductor layer, a plurality of first semiconductor regions of the first conductivity type, selectively provided in the second semiconductor layer at a surface thereof, a plurality of gate insulating films in contact with the second semiconductor layer, a plurality of gate electrodes respectively provided on the gate insulating films, a plurality of first electrodes provided on the second semiconductor layer and the first semiconductor regions, and a second electrode provided on a back surface of the semiconductor substrate.

Abstract: A method of manufacturing an insulated gate semiconductor device includes simultaneously forming a gate trench and a contact trench that respectively penetrate form a top of the electrode contact region through a main electrode contact region and a injection control region in a depth direction and respectively reach a charge transport region, the contact trench being disposed at a position laterally separated from the gate trench in a plan view; and embedding a gate electrode inside the gate trench with a gate insulating film interposed therebetween, thereby forming an insulated gate structure, and simultaneously embedding an injection suppression region inside the contact trench, the gate electrode and the injection suppression region being both made of a second semiconductor material having a narrower bandgap than a bandgap of the first semiconductor material of the charge transport region.

Abstract: First p+-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+-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+-type regions are each provided between (mesa region) adjacent trenches, separate from the first p+-type regions and the trenches. Drain-side edges of the second p+-type regions are positioned closer to a source side than are drain-side edges of the first p+-type regions. In each mesa region, an n+-type region is provided separate from the first p+-type regions and the trenches. The n+-type regions are adjacent to and face the second p+-type regions in the depth direction.

Abstract: Provided are: injection control regions of a second conductivity type provided on a charge transport region of a first conductivity type; main electrode regions of the first conductivity type provided on the injection control regions; insulated gate electrode structures going through the main electrode region and the injection control regions in the depth direction; an injection suppression region going through the main electrode regions and the injection control regions in the depth direction so as to form a pn junction in a path leading to the charge transport region, the injection suppression region including a semiconductor material with a narrower bandgap than a material of the charge transport region; and a contact protection region of the second conductivity type contacting the bottom surface of the injection suppression region.

Abstract: In a silicon carbide semiconductor device and a silicon carbide semiconductor circuit device equipped with the silicon carbide semiconductor device, a gate leak current that flows when negative voltage with respect to the potential of a source electrode is applied to the gate electrode is limited to less than 2×10?11 A and the gate leak current is limited to less than 3.7×10?6 A/m2.

Abstract: A silicon carbide semiconductor device, including a semiconductor substrate having first and second epitaxial layers. The second epitaxial layer is formed on a first main surface of the semiconductor substrate, and includes first and second semiconductor regions, selectively provided in a surface layer of the second epitaxial layer respectively in the active region and the border region, and a third semiconductor region. The semiconductor device further includes a trench penetrating the first and third semiconductor regions to reach the first epitaxial layer, a gate electrode provided in the trench via a gate insulating film, a first electrode electrically connected to the first and third semiconductor regions, and a second electrode provided at a second main surface of the semiconductor substrate. The second semiconductor region is separate from the first semiconductor region.

Abstract: A semiconductor device includes a semiconductor substrate of a first conductivity type, a first semiconductor layer of the first conductivity type, a second semiconductor layer of a second conductivity type, a first semiconductor region of the first conductivity type, a gate electrode provided via a gate insulating film, an interlayer insulating film, and a barrier metal. At a temperature T (K) and where a guaranteed time of no negative bias temperature instability is L (h), a surface density tTi1 of Ti contained in the barrier metal satisfies: t Ti ? ? 1 > 1 1.58 × 10 5 ? { ln ? ( L 1.74 × 10 - 8 ) + Ea 473 × k - Ea kT } where, k is Boltzmann's constant, and Ea is activation energy satisfying 1.0 (eV)<Ea<1.5 (eV).

Abstract: In a MOS silicon carbide semiconductor device and a silicon carbide semiconductor circuit device equipped with the silicon carbide semiconductor device, a gate leak current that flows when negative voltage with respect to the potential of the source electrode is applied to the gate electrode is limited to less than 2×10?11 A. The negative voltage applied to the gate electrode is limited to ?3V or lower relative to the potential of the source electrode.

Abstract: A semiconductor device includes lower and upper parallel pn structures. The lower parallel pn structure is disposed at a first semiconductor layer and includes lower first columns of a first conductivity type and lower second columns of a second conductivity type, the lower first and second columns each having a stripe shape, extending in a first direction and being disposed repeatedly alternating with one another in a plane parallel to a front surface. The upper parallel pn structure is disposed at the lower parallel pn structure and includes upper first columns of the first conductivity type and upper second columns of the second conductivity type, the upper first and second columns each having a stripe shape, extending in a second direction different than the first direction and disposed repeatedly alternating with one another in a plane parallel to the front surface.

Abstract: A method of manufacturing a semiconductor device includes providing a silicon carbide (SiC) substrate, forming a SiC layer on a front surface of the SiC substrate, selectively forming a first region in the SiC layer at a surface thereof, forming a source region and a contact region in the first region, forming a gate insulating film on the SiC layer and on a portion of the first region between the SiC layer and the source region, forming a gate electrode on the gate insulating film above the portion of the first region, forming an interlayer insulating film covering the gate electrode, forming a source electrode electrically connected to the source region and the contact region, forming a drain electrode on a back surface of the SiC substrate, forming a barrier film on and covering the interlayer insulating film, and forming a metal electrode on the source electrode and the barrier film.

Abstract: A semiconductor device, including a semiconductor substrate, a semiconductor layer disposed on a surface of the semiconductor substrate, a first semiconductor region disposed in the semiconductor layer at a surface thereof, a source region and a second semiconductor region disposed in the first semiconductor region at a surface thereof, a source electrode contacting the source region and the second semiconductor region, a gate insulating film disposed on the surface of the semiconductor layer and covering a portion of the first semiconductor region between the source region and the semiconductor layer, a gate electrode disposed on a surface of the gate insulating film, a drain electrode disposed on another surface of the semiconductor substrate, and a third semiconductor region, which has an impurity concentration higher than that of the first semiconductor region, formed in the semiconductor layer at the surface thereof and being electrically connected to the source electrode.

Abstract: A trench gate MOSFET has at an n-type current spreading region between an n?-type drift region and a p-type base region, a first p+-type region facing a bottom of a trench, and a second p+-type region disposed between adjacent trenches. The first and the second p+-type regions extend parallel to a first direction in which the trench extends and are partially connected by a p+-type connecting portion and thus, disposed in a ladder shape when viewed from the front surface of a semiconductor substrate. The second p+-type region has at a portion of a surface on a drain side, a recessed portion that is recessed toward a source side. One or more recessed portions is provided between connection sites in the second p+-type region for connection with the p+-type connecting portions that are adjacent to each other in the first direction X.

Abstract: A semiconductor device includes in an active region in which current flows, an n+-type silicon carbide epitaxial layer of a low concentration and formed on an n+-type silicon carbide substrate; a p-type channel region constituting a channel region; a trench contacting the p-type channel region and having embedded therein an oxide film and a gate electrode; a p+-type base layer arranged beneath the trench; a third n-type CSL layer region contacting the p-type channel region; a second n-type CSL layer region having a maximum impurity concentration higher than that of the third n-type CSL layer region, the maximum impurity concentration being farther on a substrate front side than a top of the p+-type base layer arranged beneath the trench is; and a first n-type CSL layer region contacting the second n-type CSL layer region and having a maximum impurity concentration lower than that of the second n-type CSL layer region.

Abstract: A semiconductor device includes: a semiconductor substrate of a first conductivity type; a first semiconductor layer of the first conductivity type; a second semiconductor layer of a second conductivity type; a first semiconductor region of the first conductivity type; a trench; a second semiconductor region of the second conductivity type; a third semiconductor region of the second conductivity type; and a fourth semiconductor region of the first conductivity type. The second semiconductor region is selectively provided inside the first semiconductor layer, and the third semiconductor region is selectively provided inside the first semiconductor layer and contacts a bottom surface of the trench. The fourth semiconductor region is provided perpendicularly to a lengthwise direction of the trench in a plan view and is located at a depth position that is deeper than the second semiconductor region.

Abstract: A gate pad includes a first portion disposed in a gate pad region and a second portion continuous with the first portion and disposed in a gate resistance region. The gate pad has a planar shape in which the second portion protrudes from the first portion. A gate polysilicon layer provided on a front surface of a semiconductor substrate via a gate insulating film is disposed between the semiconductor substrate and an interlayer insulating film, has a surface area that is at least equal to a surface area of the gate pad, and faces the gate pad in a depth direction. The gate polysilicon layer has a planar outline similar to that of the gate pad and includes continuous first and second portions, the first portion facing the first portion of the gate pad overall, and a second portion facing the second portion of the gate pad.

Abstract: A silicon carbide semiconductor device, including a semiconductor substrate having first and second epitaxial layers. The second epitaxial layer is formed on a first main surface of the semiconductor substrate, and includes first and second semiconductor regions, selectively provided in a surface layer of the second epitaxial layer respectively in the active region and the border region, and a third semiconductor region. The semiconductor device further includes a trench penetrating the first and third semiconductor regions to reach the first epitaxial layer, a gate electrode provided in the trench via a gate insulating film, a first electrode electrically connected to the first and third semiconductor regions, and a second electrode provided at a second main surface of the semiconductor substrate. The second semiconductor region is separate from the first semiconductor region.

Abstract: A MOS gate having a trench gate structure is formed on the front surface side of a silicon carbide substrate. A gate trench of the trench gate structure goes through an n+ source region and a p-type base region and reaches an n? drift region. Between adjacent gate trenches, a first p+ region that goes through the p-type base region in the depth direction and reaches the n? drift region is formed at a position separated from the gate trenches. The first p+ region is formed directly beneath a p++ contact region. The width of the first p+ region is less than the width w1 of the gate trench. A second p+ region is formed at the bottom of the gate trench. The first and second p+ regions are silicon carbide epitaxial layers.