Abstract: A semiconductor device includes a current spreading region of the first conductivity type provided on a drift layer and having a higher impurity density than the drift layer; a base region of a second conductivity type provided on the current spreading region; a base contact region of the second conductivity type provided in a top part of the base region and having a higher impurity density than the base region; and an electrode contact region of the first conductivity type provided in a top part of the base region that is laterally in contact with the base contact region, the electrode contact region having a higher impurity density than the drift layer, wherein a density of a second conductivity type impurity element in the base contact region is at least two times as much as a density of a first conductivity type impurity element in the electrode contact region.

Abstract: In a MOS silicon carbide semiconductor device and a silicon carbide semiconductor circuit device equipped with the silicon carbide semiconductor device, a gate leak current that flows when negative voltage with respect to the potential of the source electrode is applied to the gate electrode is limited to less than 2×10?11 A. The negative voltage applied to the gate electrode is limited to ?3V or lower relative to the potential of the source electrode.

Abstract: A semiconductor device includes a current spreading region of the first conductivity type provided on a drift layer and having a higher impurity density than the drift layer; a base region of a second conductivity type provided on the current spreading region; a base contact region of the second conductivity type provided in a top part of the base region and having a higher impurity density than the base region; and an electrode contact region of the first conductivity type provided in a top part of the base region that is laterally in contact with the base contact region, the electrode contact region having a higher impurity density than the drift layer, wherein a density of a second conductivity type impurity element in the base contact region is at least two times as much as a density of a first conductivity type impurity element in the electrode contact region.

Abstract: In an inactive region of an active region, a gate pad, a gate poly-silicon layer, and a gate finger are provided at a front surface of a semiconductor substrate, via an insulating film. The gate poly-silicon layer is provided beneath the gate pad, sandwiching the insulating film therebetween. The gate pad, the gate poly-silicon layer, a gate finger, gate electrodes of a trench gate structure, a gate finger, and a second measurement pad are electrically connected in the order stated. As a result, the gate electrodes where parasitic resistance occurs and the gate poly-silicon layer where built-in resistance occurs are connected in series between the second measurement pad and the gate pad. A resistance value of the overall gate resistance that is a combined resistance of the built-in resistance and the parasitic resistance may be measured by the second measurement pad.

Abstract: A method for producing a semiconductor power device, includes forming a gate trench from a surface of a semiconductor layer toward an inside thereof. A first insulation film is formed on an inner surface of the gate trench. The method also includes removing a part on a bottom surface of the gate trench in the first insulation film. A second insulation film having a dielectric constant higher than SiO2 is formed in such a way as to cover the bottom surface of the gate trench exposed by removing the first insulation film.

Abstract: A silicon carbide semiconductor device includes a silicon carbide semiconductor substrate, a first semiconductor layer and a first semiconductor region each of a first conductivity type, and a first base region, a second semiconductor layer and a second semiconductor region each of a second conductivity type. The first base region opposes the second semiconductor region in a depth direction. A distribution of point defects in a depth direction from a first surface of the second semiconductor region, opposite a second surface of the second semiconductor region facing toward a front surface of the silicon carbide semiconductor substrate has two peaks at positions deeper than an interface between the first semiconductor layer and the first base region, where a first peak at a deeper position of the two peaks has a greater quantity of the point defects than does a second peak at a shallower position of the two peaks.

Abstract: A portion of a source electrode exposed by an opening in a passivation film is used as a portion of a source pad. A first portion of the source pad includes a plating film formed by a material that is harder than a material of the source electrode. During screening, a probe needle that is a metal contact contacts the plating film that is on the first portion of the source pad. A second portion of the source pad has a layer structure different from that of the first portion of the source pad and in a second direction parallel to the front surface of the semiconductor chip, is disposed adjacently to and electrically connected to the first portion of the source pad. A bonding wire is wire bonded to the second portion of the source pad after an inspection process of the semiconductor chip.

Abstract: On a front surface of a silicon carbide semiconductor substrate of a first conductivity type, a first semiconductor layer of the first conductivity type having an impurity concentration lower than an impurity concentration of the silicon carbide semiconductor substrate is formed. A base region of a second conductivity type is selectively formed in the first semiconductor layer. A second semiconductor layer of the second conductivity type is formed on a surface of the first semiconductor layer. A first semiconductor region of the first conductivity type is selectively formed in a surface layer of the second semiconductor layer. The base region is formed by implanting an impurity of the second conductivity type from an angle that relative to a perpendicular to the silicon carbide semiconductor substrate, is three degrees or more.

Abstract: A gate pad is includes a first portion disposed in a gate pad region and a second portion disposed in a gate resistance region and connected to the first portion, the gate pad has a planar shape in which the second portion protrudes from the first portion. A gate polysilicon layer disposed on a front surface of a semiconductor substrate via a gate insulating film, between the semiconductor substrate and an interlayer insulating film, has a surface area at least equal to that of the gate pad and opposes an entire surface of the gate pad in a depth direction. ESD capability of a first region where the gate pad is provided is greater than ESD capability of a second region where a gate resistance is provided and is greater than ESD capability of a third region where a MOS structure of an active region is provided.

Abstract: A semiconductor device includes: an active area including a drift layer of a first conductivity type; and a voltage blocking area arranged around the active area and including an field relaxation region having a second conductivity type, being provided in an upper portion of the drift layer, wherein a depth of the field relaxation region decreases toward outside, and a spatial-modulation portion is provided at an outer end of the field relaxation region.

Abstract: An insulated gate semiconductor device includes p+ gate bottom protection regions embedded in a drift layer at the bottoms of trenches that goes through n+ source regions and p-type base regions, and p+ base bottom embedded regions embedded in the drift layer below the base regions. The base bottom embedded regions have trapezoidal shapes due to a channeling phenomenon, and the bottom surfaces of the base bottom embedded regions are deeper than the bottom surfaces of the gate bottom protection regions.

Abstract: A semiconductor device, including a first semiconductor layer of the first conductivity type formed on a semiconductor substrate, a first semiconductor region of the first conductivity type, a first base region of a second conductivity type and a first base region of a second conductivity type that are respectively selectively provided in the first semiconductor layer, a second semiconductor layer of the second conductivity type provided on the first semiconductor layer, a second semiconductor region of the first conductivity type selectively provided in the second semiconductor layer, a trench that penetrates the second semiconductor layer and the second semiconductor region, a gate electrode provided in the trench via a gate insulating film, an interlayer insulating film provided on the gate electrode, a first electrode in contact with the second semiconductor layer and the second semiconductor region, and a second electrode provided on a back surface of the semiconductor substrate.

Abstract: A method for producing a semiconductor power device, includes forming a gate trench from a surface of a semiconductor layer toward an inside thereof. A first insulation film is formed on an inner surface of the gate trench. The method also includes removing a part on a bottom surface of the gate trench in the first insulation film. A second insulation film having a dielectric constant higher than SiO2 is formed in such a way as to cover the bottom surface of the gate trench exposed by removing the first insulation film.

Abstract: 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.

Abstract: This semiconductor device includes: an n-type SiC drift layer; a p-type base region; an n-type source region selectively embedded in the top part of the base region; p-type base contact regions selectively embedded in the top part of the base region so as to form a first gap with the source region along the <11-20> direction; a gate electrode provided via a gate insulating film; and an n-type drain region. The top surface of the drain region has an off-angle relative to the <11-20> direction towards the <0001> direction, and an alignment mark for positioning is formed on the top surface. The drift layer and the base region are epitaxially grown films, and a width wg of the first gap is set in accordance with a positional deviation width of the alignment mark caused by the off-angle and epitaxial growth.

Abstract: 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.

Abstract: In a trench-gate MOSFET, between a channel and an n+-type source region, an n-type shunt resistance region is provided in contact with the n+-type source region and the channel. The n+-type source region is disposed at a position separated from a gate insulating film at a side wall of a trench, in a direction parallel to a front surface of a semiconductor substrate. The n-type shunt resistance region is disposed, positioned deeper toward a drain electrode than is a front surface of the semiconductor substrate and shallower toward a source electrode than is the channel, and reaches a position deeper toward the drain electrode from the front surface of the semiconductor substrate than is the n+-type source region. The n-type shunt resistance region is a resistor for reducing current between the drain and the source when a large current exceeding a rated current flows during a short circuit.

Abstract: A semiconductor device includes a MOSFET including a PN junction diode. A unipolar device is connected in parallel to the MOSFET and has two terminals. A first wire connects the PN junction diode to one of the two terminals of the unipolar device. A second wire connects the one of the two terminals of the unipolar device to an output line, so that the output line is connected to the MOSFET and the unipolar device via the first wire and the second wire. In one embodiment the connection of the first wire to the diode is with its anode, and in another the connection is with the cathode.

Abstract: A trench gate MOSFET has at an n-type current spreading region between an n?-type drift region and a p-type base region, a first p+-type region facing a bottom of a trench, and a second p+-type region disposed between adjacent trenches. The first and the second p+-type regions extend parallel to a first direction in which the trench extends and are partially connected by a p+-type connecting portion and thus, disposed in a ladder shape when viewed from the front surface of a semiconductor substrate. The second p+-type region has at a portion of a surface on a drain side, a recessed portion that is recessed toward a source side. One or more recessed portions is provided between connection sites in the second p+-type region for connection with the p+-type connecting portions that are adjacent to each other in the first direction X.

Abstract: A semiconductor device includes: a semiconductor substrate of a first conductivity type; a first semiconductor layer of the first conductivity type; a second semiconductor layer of a second conductivity type; a first semiconductor region of the first conductivity type; a trench; a second semiconductor region of the second conductivity type; a third semiconductor region of the second conductivity type; and a fourth semiconductor region of the first conductivity type. The second semiconductor region is selectively provided inside the first semiconductor layer, and the third semiconductor region is selectively provided inside the first semiconductor layer and contacts a bottom surface of the trench. The fourth semiconductor region is provided perpendicularly to a lengthwise direction of the trench in a plan view and is located at a depth position that is deeper than the second semiconductor region.