A semiconductor device is disclosed. In a surface layer of a front surface of an n-type semiconductor substrate, an anode layer is provided in an element activation portion and an annular p-type guard ring and an n-type high-concentration surface region are provided in an annular termination breakdown voltage region which surrounds the outer circumference of the anode layer. The impurity concentration of the n-type high-concentration surface region is higher than that of the semiconductor substrate and is lower than that of the p-type guard ring. The depth of the n-type high-concentration surface region is less than that of the guard ring. The anode layer and the guard ring are formed while the oxygen concentration of the semiconductor substrate is set to be equal to or more than 110.sup.16/cm.sup.3 and equal to or less than 110.sup.18/cm.sup.3.

A resin-sealed semiconductor device 10 of the present invention includes: a mesa-type semiconductor element 100 which includes a mesa-type semiconductor base body having a pn-junction exposure portion in an outer peripheral tapered region which surrounds a mesa region, and a glass layer which covers at least the outer peripheral tapered region; and a molding resin 40 which seals the mesa-type semiconductor element 100, wherein the mesa-type semiconductor element 100 includes a glass layer which substantially contains no Pb as the glass layer. The resin-sealed semiconductor device of the present invention can acquire higher resistance to a reverse bias at a high temperature than a conventional resin-sealed semiconductor device, although the resin-sealed semiconductor device of the present invention has the structure where the mesa-type semiconductor element is molded with a resin in the same manner as the conventional resin-sealed semiconductor device.

A semiconductor device includes at least one highly doped region of an electrical device arrangement formed in a semiconductor substrate and a contact structure including an NTC (negative temperature coefficient of resistance) portion arranged adjacent to the at least one highly doped region at a front side surface of the semiconductor substrate. The NTC portion includes a negative temperature coefficient of resistance material.

A diode is integrated on a semiconductor chip having anode and cathode surfaces opposite to each other. The diode comprises a cathode region extending inwardly from the cathode surface, a drift region extending between the anode surface and the cathode region, and a plurality of anode regions extending from the anode surface in the drift region. The diode further comprises a cathode electrode coupled with the cathode region, and an anode electrode that contacts one or more contacted anode regions of said anode regions and is electrically insulated from one or more floating anode regions of the anode regions. The diode is configured so that charge carriers are injected from the floating anode regions into the drift region in response to applying of a control voltage exceeding a threshold voltage.

According to one embodiment, a semiconductor device includes an n-type semiconductor layer, a first electrode, and a nitride semiconductor layer. The n-type semiconductor layer includes diamond. The nitride semiconductor layer is provided between the n-type semiconductor layer and the first electrode. The nitride semiconductor layer includes Al.sub.xGa.sub.1xN (0x1) and is of n-type.

A transistor cell includes a drift region, a source region, and a body region arranged between the source region and the drift region in a semiconductor body. A drain region is below the drift region. An insulated gate trench extends into the drift region. A diode region extends deeper into the drift region than the insulated gate trench and partly under the insulated gate trench so as to form a pn junction with the drift region below a bottom of the insulated gate trench. The body region adjoins a first sidewall of the insulated gate trench and the diode region adjoins a second sidewall of the insulated gate trench opposite the first sidewall so that the body region of the transistor cell and a channel region including a region of the body region extending along the first sidewall are separated from the diode region by the insulated gate trench.

A method of manufacturing a fin diode structure includes providing a substrate, forming a doped well in said substrate, forming at least one doped region of first conductivity type or at least one doped region of second doped type in said doped well, performing an etching process to said doped region of first conductivity type or said doped region of second conductivity type to form a plurality of fins on said doped region of first conductivity type or on said doped region of second conductivity type, forming shallow trench isolations between said fins, and performing a doping process to said fins to form fins of first conductivity type and fins of second conductivity type.

A diode includes a cell field, an intermediate field and a peripheral filed. The cell filed includes at least one first anode region of p-type; at least one pillar region of n-type and in contact with the anode electrode; a barrier region of n-type and in contact with the first anode region and the pillar region from a rear surface side; and a first intermediate region of p-type, in contact with the barrier region from the rear surface side. The intermediate field includes: a second anode region of p-type and in Ohmic contact with the anode electrode, a hole suppression region being in contact with the anode electrode; and a second intermediate region of p-type, in contact with the second anode region and the hole suppression region from the rear surface side. The barrier region is not located in the intermediate field.

The invention provides a semiconductor device. The semiconductor device includes a buried oxide layer disposed on a substrate. A semiconductor layer having a first conduction type is disposed on the buried oxide layer. A first well doped region having a second conduction type is disposed in the semiconductor layer. A cathode doped region having the second conduction type is disposed in the first well doped region. A first anode doped region having the first conduction type is disposed in the first well doped region, separated from the cathode doped region. A first distance from a bottom boundary of the first anode doped region to a top surface of the semiconductor layer is greater than a second distance from the bottom boundary to an interface between the semiconductor layer and the buried oxide layer.

Switching loss is reduced. A first surface of a semiconductor substrate has a portion included in an IGBT region and a portion included in a diode region. Trenches formed in the first surface include a gate trench and a boundary trench disposed between the gate trench and the diode region. A fourth layer of the semiconductor substrate is provided on the first surface and has a portion included in the diode region. The fourth layer includes a trench-covering well region that covers the deepest part of the boundary trench, a plurality of isolated well regions, and a diffusion region that connects the trench-covering well region and the isolated well regions. The diffusion region has a lower impurity concentration than that of the isolated well regions. A first electrode is in contact with the isolated well regions and away from the diffusion region.