There is disclosed the integration of a Schottky diode with a MOSFET, more in detail there is a free-wheeling Schottky diode and a power MOSFET on top of a buried grid material structure. Advantages of the specific design allow the whole surface area to be used for MOSFET and Schottky diode structures, the shared drift layer is not limited by Schottky diode or MOSFET design rules and therefore, one can decrease the thickness and increase the doping concentration of the drift layer closer to a punch through design compared to the state of the art. This results in higher conductivity and lower on-resistance of the device with no influence on the voltage blocking performance. The integrated device can operate at higher frequency. The risk for bipolar degradation is avoided.

A trench-gate MOSFET with electric field shielding region, has a substrate; a source electrode; a drain electrode; a semiconductor region with a first doping type formed on the substrate; a trench-gate, a plurality of electric field shielding regions with a second doping type formed under a surface of the semiconductor region, wherein the electric field shielding region intersects the trench-gate at an angle; a source electrode region formed on both sides of the trench-gate is divided into a plurality of source electrode sub-regions by the plurality of electric field shielding regions.

A semiconductor device includes a junction field effect transistor (JFET) including a source electrode, a drain electrode, and a gate electrode, and a metal oxide semiconductor field effect transistor (MOSFET) including a source electrode, a drain electrode, and a gate electrode. The JFET and the MOSFET are cascode-connected such that the source electrode of the JFET and the drain electrode of the MOSFET are electrically connected. A gate voltage dependency of the JFET or a capacitance ratio of a mirror capacitance of the MOSFET to an input capacitance of the MOSFET is adjusted in a predetermined range.

A wide gap semiconductor device has: a wide gap semiconductor layer; and a metal layer 20 provided on the wide gap semiconductor layer. The metal layer 20 has a single crystal layer 21 in an interface region at an interface with the wide gap semiconductor layer. When it is assumed that a lattice constant, in an equilibrium state, of a metal constituting the metal layer 20 is L, the single crystal layer 21 in the interface region includes a first region in which a lattice constant L1 is smaller than L by 1.5% to 8%.

Disclosed is a silicon carbide MOSFET device and a manufacturing method thereof. The manufacturing method comprises: forming a source region in an epitaxial layer; forming a body region in the epitaxial layer; forming a gate structure, comprising a gate dielectric layer, a gate conductor layer and an interlayer dielectric layer; forming an opening in the interlayer dielectric layer to expose the source region; forming a source contact connected to the source region via the opening, wherein an ion implantation angle of the ion implantation process is controlled to make a transverse extension range of the body region larger than a transverse extension range of the source region, so that a channel that extends transversely is formed by a portion, which is peripheral to the source region, of the body region, and at least a portion of the gate conductor layer is located above the channel.

A semiconductor device includes a MOSFET including a drift layer, a channel layer, a trench gate structure, a source layer, a drain layer, a source electrode, and a drain electrode. The trench gate structure includes a trench penetrating the channel layer and protruding into the drift layer, a gate insulating film disposed on a wall surface of the trench, and a gate electrode disposed on the gate insulating film. A portion of the trench protruding into the drift layer is entirely covered with a well layer, and the well layer is connected to the channel layer.

A field effect transistor includes a semiconductor substrate and multiple trenches disposed at a top surface of the semiconductor substrate. The trenches extend in a first direction at the top surface of the semiconductor substrate, and are disposed to be spaced apart in a direction perpendicular to the first direction. Connection regions are disposed below body regions. The connection regions extend in a second direction intersecting the first direction in a top view of the semiconductor substrate, and are spaced apart in a direction perpendicular to the second direction. Field relaxation regions are disposed below the connection regions and the trenches. The field relaxation regions extend in a third direction intersecting the first direction and the second direction in the top view of the semiconductor substrate, and are spaced apart in a direction perpendicular to the third direction.

A SiC epitaxial wafer includes a SiC substrate and an epitaxial layer laminated on the SiC substrate, wherein the epitaxial layer contains an impurity element which determines the conductivity type of the epitaxial layer and boron which has a conductivity type different from the conductivity type of the impurity element, and the concentration of boron in the center of the epitaxial layer is less than 5.0×10.sup.12 cm.sup.−3.

A semiconductor device includes an N+ type substrate, an N− type layer disposed on a first surface of the N+ type substrate and having a trench opened to a surface opposite to the surface facing the N+ type substrate, a P type region disposed in the N− type layer and disposed on a side surface of the trench, a gate electrode disposed in the trench, and a source electrode and a drain electrode insulated from the gate electrode. The N− type layer includes a P type shield region covering a bottom surface and an edge of the trench.

A semiconductor device includes: a substrate (10); a semiconductor layer (20) disposed on a main surface of this substrate (10); and a first main electrode (30) and a second main electrode (40), which are disposed on the substrate (10) separately from each other with the semiconductor layer (20) sandwiched therebetween and are individually end portions of a current path of a main current flowing in an on-state. The semiconductor layer (20) includes: a first conductivity-type drift region (21) through which a main current flows; a second conductivity-type column region (22) that is disposed inside the drift region (21) and extends in parallel to a current path; and an electric field relaxation region (23) that is disposed in at least a part between the drift region (21) and the column region (22) and is either a low-concentration region in which an impurity concentration is lower than in the same conductivity-type adjacent region or a non-doped region.