The application relates to a semiconductor die having a semiconductor body including an active region, an insulation layer on the semiconductor body, and a sodium stopper formed in the insulation layer. The sodium stopper is arranged in an insulation layer groove which intersects the insulation layer vertically and extends around the active region. The sodium stopper is formed of a tungsten material filling the insulation layer groove.

The present invention introduces a new shielded gate trench MOSFETs wherein epitaxial layer having special multiple stepped epitaxial (MSE) layers with different doping concentrations decreasing in a direction from substrate to body regions, wherein each of the MSE layers has uniform doping concentration as grown. Specific on-resistance is significantly reduced with the special MSE structure. Moreover, in sore preferred embodiment, an MSO (multiple stepped oxide) structure is applied to the shielded gate structure to further reduce the specific on-resistance and enhance device ruggedness.

A power semiconductor device includes an active region and an edge termination region surrounding the active region. A field plate structure arranged around the active region includes at least one electrically conductive track electrically connected to a first potential of a first load terminal at a first joint and, at a second joint, electrically connected to a second potential of a second load terminal. The track forms at least n crossings, wherein n is greater 5, with a straight virtual line that extends from the active region towards an edge of the edge termination region. The difference in potential between adjacent two crossings increases in at least 50% of the length of the virtual line, and/or the difference in potential within, with respect to the active region, the first 20% of the length of virtual line is less than 10% of the total difference in potential along the virtual line.

A method of manufacturing a silicon carbide semiconductor device includes formation of an electrode and formation of a gate wiring. The electrode is formed to be electrically connected to a base layer and an impurity region included in a semiconductor substrate through a first contact hole. The gate wiring is formed to be electrically connected to a connection wiring through a second contact hole, and is made of material capable of deoxidizing an oxide film. The oxide film is removed by deoxidizing the oxide film formed on the connection wiring to remove the oxygen from the oxide film into the gate wiring through heating treatment for the gate wiring in the formation of the gate wiring or after the formation of the gate wiring.

A semiconductor device according to the present disclosure includes: a gate electrode provided in a gate trench and provided so as to oppose a source region via a gate insulating film; a first bottom protection region of a second conductivity type provided below the gate insulating film; a plurality of first connection regions of the second conductivity type provided at a first interval in an extension direction of the gate trench and electrically connecting the first bottom protection region and a body region; a Schottky electrode provided in a Schottky trench; a second bottom protection region of the second conductivity type provided below the Schottky electrode; and a plurality of second connection regions of the second conductivity type provided at a second interval smaller than the first interval in an extension direction of the Schottky trench and electrically connecting the second bottom protection region and the body region.

A silicon carbide layer has an active region and an outer peripheral region arranged along an outer periphery of the active region in an in-plane direction. First well regions are arranged in the active region. A second well region is arranged in the outer peripheral region. Ohmic electrodes are arranged on a second surface of the silicon carbide layer, are connected to a source electrode, are electrically and ohmically connected to the first well regions, and have surface regions ohmically contacting a part forming the second surface of the silicon carbide layer and having a second conductivity type. The active region includes a standard region part and a thinned region part between the standard region part and the outer peripheral region. The surface regions are arranged at surface density lower in the thinned region part than in the standard region part in a plan view.

A semiconductor device includes: a semiconductor layer; a gate trench formed in the semiconductor layer; an insulating layer formed on the semiconductor layer; a gate electrode buried in the gate trench via the insulating layer; a gate wiring formed on the insulating layer and electrically connected to the gate electrode; and a protection trench formed in the semiconductor layer, wherein the semiconductor layer includes an outer peripheral region including outer edges of the semiconductor layer in a plan view and an inner region surrounded by the outer peripheral region, wherein the gate trench includes an outer peripheral gate trench portion arranged in the outer peripheral region and surrounded by the protection trench in a plan view, and wherein the outer peripheral gate trench portion and the protection trench are formed in a closed annular shape along the outer edges of the semiconductor layer in the outer peripheral region.

A semiconductor device includes a semiconductor layer of a first conductivity type having a device forming region and an outside region, an impurity region of a second conductivity type formed in a surface layer portion of a first main surface in the device forming region, a field limiting region of a second conductivity type formed in the surface layer portion in the outside region and having a impurity concentration higher than that of the impurity region, and a well region of a second conductivity type formed in a region between the device forming region and the field limiting region in the surface layer portion in the outside region, having a bottom portion positioned at a second main surface side with respect to bottom portions of the impurity region and the field limiting region, and having a impurity concentration higher than that of the impurity region.

A manufacturing method of an electronic device includes: forming a drift layer of an N type; forming a trench in the drift layer; forming an edge-termination structure alongside the trench by implanting dopant species of a P type; and forming a depression region between the trench and the edge-termination structure by digging the drift layer. The steps of forming the depression region and the trench are carried out at the same time. The step of forming the depression region comprises patterning the drift layer to form a structural connection with the edge-termination structure having a first slope, and the step of forming the trench comprises etching the drift layer to define side walls of the trench, which have a second slope steeper than the first slope.

In an embodiment, a method of forming a field plate in an elongate active trench of a transistor device is provided. The elongate active trench includes a first insulating material lining the elongate active trench and surrounding a gap and first conductive material filling the gap. The method includes selectively removing a first portion of the first insulating material using a first etch process, selectively removing a portion of the first conductive material using a second etch process, and forming a field plate in a lower portion of the elongate active trench and selectively removing a second portion of the first insulating material using a third etch process. The first etch process is carried out before the second etch process and the second etch process is carried out before the third etch process.