The sense region is spaced from the active region. The isolation trench surrounds the sense region and isolates the sense region from the active region. The active region is provided with a first gate trench defined by a first side surface and a first bottom surface continuing to the first side surface. The first insulating film is in contact with both the first side surface and the first bottom surface. The first conductor is provided on the first insulating film. The second insulating film is provided in the isolation trench. The second conductor is provided on the second insulating film. The isolation trench reaches a first impurity region. The first insulating film is made of a material identical to that of the second insulating film. The first conductor is made of a material identical to that of the second conductor and is electrically isolated from the second conductor.

A main semiconductor device element is a vertical MOSFET with a trench gate structure, containing silicon carbide as a semiconductor material, and having first and second p.sup.+-type regions that mitigate electric field applied to bottoms of trenches. The first p.sup.+-type regions are provided separate from the p-type base regions and face the bottoms of the trenches in a depth direction. The first p.sup.+-type regions are disposed at an interval that is at most 1.0 μm, in a first direction that is a direction in which gate electrodes extend. The second p.sup.+-type regions are provided between adjacent trenches of the trenches, separate from the first p.sup.+-type regions and the trenches, and in contact with the p-type base regions. In the first direction that is the direction in which the trenches, the second p.sup.+-type regions extend in a linear shape having a length that is substantially equal to that of the trenches.

Provided is a semiconductor apparatus comprising: an emitter region having a first conductivity type provided on a front surface of a semiconductor substrate; a first gate trench part and a second gate trench part in contact with the emitter region; a first emitter non-contact trench part and a second emitter non-contact trench part out of contact with the emitter region; a gate pad for setting the first gate trench part, the second gate trench part, the first emitter non-contact trench part, and the second emitter non-contact trench part to gate potential; and a diode having an anode connected to the gate pad and a cathode connected to the first emitter non-contact trench part and the second emitter non-contact trench part, wherein the first gate trench part, the first emitter non-contact trench part, the second gate trench part, and the second emitter non-contact trench part are adjacently arranged in order.

A power element includes a substrate structure, an insulation layer, a dielectric layer, a transistor, and a plurality of zener diodes. The transistor is located in a transistor formation region of the substrate structure. The plurality of zener diodes are located in a circuit element formation region of the substrate structure and connected in series with each other. Each of the zener diodes includes a zener diode doping structure and a zener diode metal structure. The zener diode doping structure is formed on the insulation layer and is covered by the dielectric layer. The zener diode doping structure includes a P-type doped region and an N-type doped region that are in contact with each other. The zener diode metal structure is formed on the dielectric layer and partially passes through the dielectric layer to be electrically connected to the P-type doped region and the N-type doped region.

A method of manufacturing a silicon carbide device includes: forming a trench in a process surface of a silicon carbide substrate that has a body layer forming second pn junctions with a drift layer structure, wherein the body layer is between the process surface and the drift layer structure and wherein the trench exposes the drift layer structure; implanting dopants through a bottom of the trench to form a shielding region that forms a first pn junction with the drift layer structure; forming dielectric spacers on sidewalls of the trench; and forming a buried portion of an auxiliary electrode in a bottom section of the trench, the buried portion adjoining the shielding region.

A drift structure having a drift zone of a first conductivity type is formed in a SiC semiconductor body of a semiconductor component. Transistor cells each include a doping region and a source region in the SiC semiconductor body. The doping region forms a first pn junction with the drift structure and a second pn junction with the source region. The doping region is electrically connected to a first load electrode. A diode region is formed between the transistor cells and a side surface of the SiC semiconductor body. The diode region is electrically connected to the first load electrode and forms a third pn junction with the drift structure. An emitter efficiency of the diode region is higher than an emitter efficiency of the doping region.

A semiconductor device having, in a main non-operating region that is free of unit cells of a main semiconductor element, a gate insulating film and a gate electrode of a current sensing portion extending on a front surface of a semiconductor substrate, to thereby form a planar gate structure. A gate capacitance of the planar gate structure is a gate capacitance of the current sensing portion. Directly beneath the planar gate structure, at the front surface of the semiconductor substrate, a structure is provided in which, from a front side of the semiconductor substrate, a p-type region, an n-type region, and a p-type region are stacked, whereby electric field is not applied to the extended portions of the gate insulating film.

A semiconductor device includes a semiconductor substrate, a trench provided in the semiconductor substrate, a trench gate formed in the trench, a vertical transistor having the trench gate, an active region having the vertical transistor, a field region surrounding the active region and having a protection diode, and a field insulating film formed on a surface of the semiconductor substrate, the protection diode being formed on the field insulating film. The trench gate includes a first polysilicon layer and has an embedded part embedded in the trench and an extension part connected to the embedded part and extending onto the surface of the semiconductor substrate, the protection diode includes a second polysilicon layer thicker than the first polysilicon layer, and an overlapping part having the second polysilicon layer is formed on the extension part.

There is provided a technique for suppressing the operation of a parasitic transistor in a semiconductor device having a voltage sense structure. The semiconductor device includes: a semiconductor layer; a first impurity region; a second impurity region; a first semiconductor region; a second semiconductor region; a first electrode; a second electrode; and a third electrode. The second impurity region includes a low lifetime region at least under the second semiconductor region. The low lifetime region is a region having a defect density higher than that in a surface layer of the second impurity region or a region in which a heavy metal is diffused.

In a general aspect, a semiconductor device can include a semiconductor region of a first conductivity type and a well region of a second conductivity type. The well region can be disposed in the semiconductor region. An interface between the well region and the semiconductor region can define a diode junction at a depth below an upper surface of the semiconductor region. The semiconductor device can further include at least one dielectric region disposed in the semiconductor region. A dielectric region of the at least one dielectric region can have an upper surface that is disposed in the well region at a depth in the semiconductor region that is above the depth of the diode junction; and a lower surface that is disposed in the semiconductor region at a depth in the semiconductor region that is the same depth as the diode junction or below the depth of the diode junction.