A trench junction field effect transistor (trench JFET) includes a mesa region confined by first and second trenches along a first lateral direction. The first and second trenches extend into a semiconductor body from a first surface of the semiconductor body. A mesa channel region of a first conductivity type is confined, along the first lateral direction, by first and second gate regions of a second conductivity type. A first pn junction is defined by the mesa channel region and the first gate region. A second pn junction is defined by the mesa channel region and the second gate region. The mesa channel region includes, along the first lateral direction, first, second and third mesa channel sub-regions having a same extent along the first lateral direction.

A semiconductor device has: a silicon carbide semiconductor substrate of a first conductivity type; a first semiconductor layer of the first conductivity type; a first semiconductor region of a second conductivity type; a second semiconductor region of the first conductivity type; a trench; a gate insulating film; a gate electrode; a third semiconductor region of the first conductivity type, and a fourth semiconductor region of the second conductivity type. The third semiconductor region is provided between the gate insulating film on a sidewall of the trench and the first semiconductor region. The fourth semiconductor region is provided between the first semiconductor region and the third semiconductor region, and has an impurity concentration higher than that of the first semiconductor region.

A SiC SJ trench MOSFET having first and second type gate trenches for formation of gate electrodes and super junction regions is disclosed. The gate electrodes are disposed into the first type gate trenches having a thick oxide layer on trench bottom. The super junction regions are formed surrounding the second type gate trenches filled up with the thick oxide layer. The device further comprises gate oxide electric field reducing regions adjoining lower surfaces of body regions and space apart from the gate trenches.

By a first ion-implantation of a p-type impurity, first and second p.sup.+-type regions for mitigating electric field of trench bottoms are formed in surface regions of an n.sup.−-type epitaxial layer that constitutes an n.sup.−-type drift region. Thereafter, a second ion-implantation of an n-type impurity for reverting a portion of each of the first p.sup.+-type regions to the n.sup.−-type, and a third ion-implantation of an n-type impurity for an entire surface of the n.sup.−-type epitaxial layer, are performed. By the second ion-implantation, first current spreading layer (CSL) portions that constituting n-type current spreading regions are formed facing the first p.sup.+-type regions in the depth direction. By the third ion-implantation, the first CSL portions have a predetermined n-type impurity concentration, and second CSL portions constituting the n-type current spreading regions are formed between the first and second p.sup.+-type regions and are in contact with the first CSL portions.

A semiconductor device includes a semiconductor part including a first semiconductor layer of a first conductivity type and a second semiconductor layer of a second conductivity type. The second semiconductor layer is provided in the first semiconductor layer. The semiconductor part includes first and second interfaces of the first semiconductor layer and the second semiconductor layer. The first interface intersects the second interface. The second semiconductor layer includes a plurality of sub-layers stacked in a direction orthogonal to the first interface. The second interface includes interfaces of the sub-layers of the second semiconductor layer and the first semiconductor layer. The second interface extending in a second direction inclined with respect to a first direction orthogonal to the first interface.

A silicon carbide substrate is provided that includes a drift layer of a first conductivity type and a trench extending from a main surface of the silicon carbide substrate into the drift layer. First dopants are implanted through a first trench sidewall of the trench. The first dopants have a second conductivity type and are implanted at a first implant angle into the silicon carbide substrate, wherein at the first implant angle channeling occurs in the silicon carbide substrate. The first dopants form a first compensation layer extending parallel to the first trench sidewall.

A semiconductor device of the present invention includes a semiconductor layer, a gate trench that defines a source region of a first conductivity type in the semiconductor layer, a channel region of a second conductivity type of a lower part of the source region, a source trench that passes through the source region and the channel region, an impurity region of the second conductivity type of a bottom part and a side part of the source trench, a source electrode on the semiconductor layer, and a highly-concentrated impurity region of the second conductivity type, the highly-concentrated impurity region having a contact portion connected to the source electrode at a surface of the semiconductor layer, the highly-concentrated impurity region passing through the source region and extending to a position deeper than the source region, the highly-concentrated impurity region having a concentration higher than the impurity region.

A SiC Schottky rectifier with surge current ruggedness is described. The Schottky rectifier includes one or more multi-layer bodies that provide multiple types of surge current protection.

Semiconductor devices include a silicon carbide drift region having an upper portion and a lower portion. A first contact is on the upper portion of the drift region and a second contact is on the lower portion of the drift region. The drift region includes a superjunction structure that includes a p-n junction that is formed at an angle of between 10° and 30° from a plane that is normal to a top surface of the drift region. The p-n junction extends within +/−1.5° of a crystallographic axis of the silicon carbide material forming the drift region.

An insulated-gate semiconductor device, which has trenches arranged in a chip structure, the trenches defining both sidewalls in a first and second sidewall surface facing each other, includes: a first unit cell including a main-electrode region in contact with a first sidewall surface of a first trench, a base region in contact with a bottom surface of the main-electrode region and the first sidewall surface, a drift layer in contact with a bottom surface of the base region and the first sidewall surface, and a gate protection-region in contact with the second sidewall surface and a bottom surface of the first trench; and a second unit cell including an operation suppression region in contact with a first sidewall surface and a second sidewall surface of a second trench, wherein the second unit cell includes the second trench located at one end of an array of the trenches.