A semiconductor device includes: a semiconductor substrate having opposing first and second main surfaces; a plurality of transistor cells each including a source region, a drift zone, a body region separating the source region from the drift zone, a field plate trench extending into the drift zone and including a field plate, and a planar gate on the first main surface and configured to control current through a channel of the body region; a drain region at the second main surface; and a diffusion barrier structure including alternating layers of Si and oxygen-doped Si and a Si capping layer on the alternating layers of Si and oxygen-doped Si. The diffusion barrier structure may be interposed between body regions of adjacent transistor cells and/or extend along the channel of each transistor cell and/or vertically extend in the semiconductor substrate between adjacent field plate trenches.

An object of the present disclosure is to provide a trench gate type power semiconductor device that does not easily break even when stress is applied. A SiC-MOSFET includes a SiC substrate, a drift layer of a first conductive type, formed on the SiC substrate, a base region of a second conductivity type formed in a surface layer of the drift layer, a source region of the first conductivity type selectively formed in a surface layer of the base region, a trench extending through the base region and the source region and reaching the drift layer, a gate electrode embedded in the trench and having a V-shaped groove on an upper surface thereof, and an oxide film formed on an upper surface including the groove of the gate electrode, in which a bottom of the V-shape groove is deeper than the base region.

A transistor device and a method for producing thereof are disclosed. The transistor device includes: a SiC semiconductor body that includes a first semiconductor layer; a plurality of trenches each extending from a first surface of the first semiconductor layer into the first semiconductor layer; and a plurality of transistor cells each coupled to a source node. The first semiconductor layer includes a plurality of mesa regions each formed between two neighboring ones of the trenches, in each of the mesa regions, at least one of the plurality of transistor cells is at least partially integrated, each of the transistor cells is connected to the source node via a respective source contact, and each of the source contacts is arranged in a respective one of the trenches and is spaced apart from a bottom of the respective trench.

A multi-trench super junction IGBT device includes a metallization collector, a P-type substrate, a first N-type epitaxial layer located above the P-type substrate and a second N-type epitaxial layer located above the first N-type epitaxial layer. The second N-type epitaxial layer includes at least a first dummy MOS cell unit and a MOS cell unit, wherein the first dummy MOS cell unit includes a trench formed by reactive ion etching, a thermally grown gate oxide layer provided inside the trench and deposited heavily doped polysilicon located in the gate oxide layer.

In an entire intermediate region between an active region and an edge termination region, a p.sup.+-type region is provided between a p-type base region and a parallel pn layer. The p.sup.+-type region is formed concurrently with and in contact with p.sup.+-type regions for mitigating electric field near bottoms of gate trenches. The p.sup.+-type region has portions that face, respectively, n-type regions and p-type regions of a parallel pn layer in a depth direction Z and at the portions, has protrusions that protrude toward the parallel pn layer. N-type current spreading regions extend in the entire intermediate region from the active region and are between the p.sup.+-type region and the parallel pn layer, positioned between protrusions of the p.sup.+-type region. The impurity concentration of the n-type current spreading regions in the gate region is higher than that of those in other regions. Thus, avalanche capability may be enhanced.

A semiconductor device includes a backside contact and a substrate. An epitaxial field stop region may be formed on the substrate with a graded doping profile that decreases with distance away from the substrate, and an epitaxial drift region may be formed adjacent to the epitaxial field stop region. A frontside device may be formed on the epitaxial drift region.

An improved inverted field-effect-transistor semiconductor device and method of making thereof may comprise a source layer on a bottom and a drain disposed on a top of a semiconductor substrate and a vertical current conducting channel between the source layer and the drain controlled by a trench gate electrode disposed in a gate trench lined with an insulating material. A heavily doped drain region is disposed near the top of the substrate surrounding an upper portion of a shield trench and the gate trench. A doped body contact region is disposed in the substrate and surrounding a lower portion of the shield trench. A shield electrode extends upward from the source layer in the shield trench for electrically shorting the source layer and the body region wherein the shield structure extends upward to a heavily doped drain region and is insulated from the heavily doped drain region to act as a shield electrode.

A high voltage transistor structure including a substrate, a first isolation structure, a second isolation structure, a gate structure, a first source and drain region, and a second source and drain region is provided. The first isolation structure and the second isolation structure are disposed in the substrate. The gate structure is disposed on the substrate, at least a portion of the first isolation structure, and at least a portion of the second isolation structure. The first source and drain region and the second source and drain region are located in the substrate on two sides of the first isolation structure and the second isolation structure. The depth of the first isolation structure is greater than the depth of the second isolation structure.

A power device includes: a semiconductor layer, a well region, a body region, a gate, a source, a drain, a first salicide block (SAB) layer and a second SAB layer. The first SAB layer is formed on a top surface of the semiconductor layer, and is located between the gate and the drain, wherein a part of the well is located vertically below and in contact with the first SAB layer. The second SAB layer is formed vertically above and in contact with the first SAB layer.

A power device includes: a semiconductor layer, a well region, a body region, a gate, a source, a drain, a field oxide region, and a self-aligned drift region. The field oxide region is formed on an upper surface of the semiconductor layer, wherein the field oxide region is located between the gate and the drain. The field oxide region is formed by steps including a chemical mechanical polish (CMP) process step. The self-aligned drift region is formed in the semiconductor layer, wherein the self-aligned drift region is entirely located vertically below and in contact with the field oxide region.