A semiconductor device includes a nitride semiconductor layer, a source electrode, a drain electrode, and an insulating gate portion. The nitride semiconductor layer has an element part and a peripheral withstand voltage part. The source electrode is disposed adjacent to a first main surface of the nitride semiconductor layer. The drain electrode is disposed adjacent to a second main surface of the nitride semiconductor layer. The nitride semiconductor layer is formed with a first groove on the first main surface in the element part, and a second groove on the first main surface in the peripheral withstand voltage part. A JFET region is embedded in the first groove in the element part. An inclination angle of a side surface of the first groove adjacent to a channel portion of a body region is smaller than an inclination angle of a side surface of the second groove.

The semiconductor device according to one embodiment includes a semiconductor substrate having a first surface and a second surface on an opposite side of the first surface, a gate insulating film formed on the first surface, a gate formed on the first surface via the gate insulating film, a source region formed in the first surface side of the semiconductor substrate, a body region formed so as to be in contact with the source region and including a channel region, a drain region formed in the second surface side of the semiconductor substrate, and a drift region formed so as to be in contact with the second surface side of the body region and the first surface side of the drain region. The semiconductor substrate has at least one concave portion formed in the second surface and being recessed toward the first surface.

High-voltage semiconductor device and method of forming the same, the high-voltage semiconductor device includes a substrate, a gate structure, a drain, a first insulating structure and a drain doped region. The gate structure is disposed on the substrate. The drain is disposed in the substrate, at one side of the gate structure. The first insulating structure is disposed on the substrate, under the gate structure to partially overlap with the gate structure. The drain doped region is disposed in the substrate, under the drain and the first insulating structure, and the drain doped region includes a discontinuous bottom surface.

The present disclosure describes vertical transistor device and methods of making the same. The vertical transistor device includes substrate layer of first conductivity type, drift layer of first conductivity type formed over substrate layer, body region of second conductivity type extending vertically into drift layer from top surface of drift layer, source region of first conductivity type extending vertically from top surface of drift layer into body region, dielectric region including first and second sections formed over top surface, buried channel region of first conductivity type at least partially sandwiched between body region on first side and first and second sections of dielectric region on second side opposite to first side, gate electrode formed over dielectric region, and drain electrode formed below substrate layer. Dielectric region laterally overlaps with portion of body region. Thickness of first section is uniform and thickness of second section is greater than first section.

A semiconductor device including an active region protruding from an upper surface of a substrate and extending in a first horizontal direction, at least two gate electrodes extending in a second horizontal direction and crossing the active region, the second horizontal direction crossing the first horizontal direction, a source/drain region in the active region between the gate electrodes may be provided. The source/drain region includes a recess region, an outer doped layer on an inner wall of the recess region, an intermediate doped layer on the outer doped layer, and an inner doped layer on the intermediate doped layer and filling the recess region. One of the outer doped layer or the intermediate doped layer includes antimony, and the inner doped layer includes phosphorous.

Various embodiments of the present application are directed towards an integrated circuit (IC) in which a high voltage metal-oxide-semiconductor (HVMOS) device is integrated with a high voltage junction termination (HVJT) device. In some embodiments, a first drift well and a second drift well are in a substrate. The first and second drift wells border in a ring-shaped pattern and have a first doping type. A peripheral well is in the substrate and has a second doping type opposite the first doping type. The peripheral well surrounds and separates the first and second drift wells. A body well is in the substrate and has the second doping type. Further, the body well overlies the first drift well and is spaced from the peripheral well by the first drift well. A gate electrode overlies a junction between the first drift well and the body well.

In one embodiment, method of making a high voltage PMOS (HVPMOS) transistor, can include: (i) providing a P-type substrate; (ii) implanting N-type dopants in the P-type substrate; (iii) dispersing the implanted N-type dopants in the P-type substrate to form a deep N-type well; (iv) implanting P-type dopants of different doping concentrations in the deep N-type well along a horizontal direction of the deep N-type well; and (v) dispersing the implanted P-type dopants to form a composite drift region having an increasing doping concentration and an increasing junction depth along the horizontal direction of the deep N-type well.

A semiconductor device including a semiconductor element is provided. The semiconductor element includes a saturation current suppression layer formed above a drift layer and including electric field block layers arranged in a stripe manner and JFET portions arranged in a stripe manner. The electric field block layers and the JFET portions are alternately arranged. The semiconductor element includes trench gate structures. A longer direction of the trench gate structure intersects with a longer direction of the electric field block layer and a longer direction of JFET portion. The JFET portion includes a first layer having a first conductivity type impurity concentration larger than the drift layer and a second layer formed above the first layer and having a first conductivity type impurity concentration smaller than the first layer.

A method includes providing a semiconductor substrate, and forming a first N-type implant region and a second N-type implant region in the semiconductor substrate. The first N-type implant region and the second N-type implant region are separated by a portion of the semiconductor substrate. The method also includes forming a first P-type implant region in the semiconductor substrate, and performing a heat treatment process on the semiconductor substrate to form an N-type well region and a P-type well region in the semiconductor substrate. The N-type well region has a first portion, a second portion, and a third portion between the first portion and the second portion. The doping concentration of the third portion is lower than the doping concentration of the first portion and the doping concentration of the second portion.

A lateral double-diffused metal-oxide-semiconductor (LDMOS) transistor including a breakdown voltage clamp includes a drain n+ region, a source n+ region, a gate, and a p-type reduced surface field (PRSF) layer including one or more bridge portions. Each of the one or more bridge portions extends below the drain n+ region in a thickness direction. Another LDMOS transistor includes a drain n+ region, a source n+ region, a gate, an n-type reduced surface field (NRSF) layer disposed between the source n+ region and the drain n+ region in a lateral direction, a PRSF layer disposed below the NRSF layer in a thickness direction orthogonal to the lateral direction, and a p-type buried layer (PBL) disposed below the PRSF layer in the thickness direction. The drain n+ region is disposed over the PBL in the thickness direction.