Abstract: A source region of a MOSFET includes: a source contact region connected to a source pad; a source extension region adjacent to a channel region in a well region; and a source resistance control region arranged between the source extension region and the source contact region. The source resistance control region is different in an impurity concentration from the source extension region and the source contact region. These three regions are connected in series between the source pad and the channel region in the well region.

Abstract: A silicon carbide semiconductor device includes: a drift layer of a first conductivity type made of silicon carbide; a well region of a second conductivity type formed on the drift layer; a source region of a first conductivity type formed on the well region; a gate insulating film formed on an inner wall of a trench extending from a front surface of the source region through the well region, at least a part of a side surface of the gate insulating film being in contact with the drift layer; a gate electrode formed in the trench with the gate insulating film therebetween; a protective layer of the second conductivity type formed in the drift layer; and a depletion suppressing layer of the first conductivity type formed in the drift layer so as to be in contact with a side surface of the protective layer.

Abstract: A silicon carbide semiconductor device that reduces an influence of an off-angle of a silicon carbide substrate on characteristics of the semiconductor device and achieves improved operational stability and reduced resistance. In a trench-gate silicon carbide MOSFET semiconductor device, a high-concentration well region is formed in a well region, and a distance from a first sidewall surface of a trench of the silicon carbide semiconductor to the high-concentration well region is smaller than a distance from a second sidewall surface of the trench to the high-concentration well region, the second sidewall surface facing the first sidewall surface of the trench through the gate electrode.

Abstract: A silicon carbide semiconductor device capable of decreasing an ON-state resistance and improving a breakdown voltage. The silicon carbide semiconductor device includes: a drift layer of a first conductivity type made of a silicon carbide semiconductor; a depletion suppression layer of the first conductivity type formed on the drift layer and having a first conductivity type impurity concentration higher than that of the drift layer; a body region of a second conductivity type formed on the depletion suppression layer; a trench extending through the body region and the depletion suppression layer to reach the drift layer; and a gate insulation film formed along bottom and side surfaces of the trench. The depletion suppression layer has a thickness equal to or greater than 0.06 ?m and equal to or less than 0.31 ?m.

Abstract: A silicon carbide semiconductor device includes a drift layer of a first conductivity type, a source region of the first conductivity type, an active trench formed in penetration through the source region, a base region, a termination trench formed around the active trench, a gate insulating film formed on a bottom surface, a side surface of the active trench, a gate electrode embedded and formed in the active trench with the gate insulating film interposed therebetween, a protective diffusion layer of a second conductivity type formed in a lower portion of the active trench and a part of a lower portion of the termination trench and having a first impurity concentration, and a termination diffusion layer of the second conductivity type formed on an outside of the protective diffusion layer in the lower portion of the termination trench and having a second impurity concentration lower than the first impurity concentration.

Abstract: It is an object of the present invention to provide a silicon carbide semiconductor device that reduces an influence of an off-angle of a silicon carbide substrate on characteristics of the semiconductor device and achieves improved operational stability and reduced resistance. In a trench-gate silicon carbide MOSFET semiconductor device formed on the silicon carbide semiconductor substrate having the off-angle, a low-channel doped region is provided on a first sidewall surface side of the trench in a well region, and a high-channel doped region having an effective acceptor concentration lower than that of the low-channel doped region is provided on a second sidewall surface side of the trench in the well region.

Abstract: In a high speed switching power semiconductor device having a sense pad, a high voltage is generated during switching operations in well regions under the sense pad due to a displacement current flowing through its flow path with a resistance, whereby the power semiconductor device sometimes breaks down by dielectric breakdown of a thin insulating film such as a gate insulating film. In a power semiconductor device according to the invention, sense-pad well contact holes are provided on well regions positioned under the sense pad and penetrate a field insulating film thicker than the gate insulating film to connect to the source pad, thereby improving reliability.

Abstract: There is provided a trench-gate type semiconductor device that can prevent breakdown of a gate insulating film caused by a displacement current flowing into a protective diffusion layer at a portion of a trench underlying a gate electrode at a turn-off time and simultaneously improves a current density by narrowing a cell pitch. The semiconductor device has a gate electrode 7 embedded into a trench 5 penetrating a base region 3. The gate electrode 7 is disposed into a lattice shape in a planar view, and a protective diffusion layer 13 is formed in a drift layer 2a at the portion underlying thereof. At least one of blocks divided by the gate electrode 7 is a protective contact region 20 on which the trench 5 is entirely formed. A protective contact 21 for connecting the protective diffusion layer 13 at a bottom portion of the trench 5 and a source electrode 9 is disposed on the protective contact region 20.

Abstract: A silicon carbide semiconductor device that reduces an influence of an off-angle of a silicon carbide substrate on characteristics of the semiconductor device and achieves improved operational stability and reduced resistance. In a trench-gate silicon carbide MOSFET semiconductor device, a high-concentration well region is formed in a well region, and a distance from a first sidewall surface of a trench of the silicon carbide semiconductor to the high-concentration well region is smaller than a distance from a second sidewall surface of the trench to the high-concentration well region, the second sidewall surface facing the first sidewall surface of the trench through the gate electrode.

Abstract: A trench-gate type semiconductor device that can prevent breakdown of a gate insulating film caused by a displacement current flowing into a protective diffusion layer at a portion of a trench underlying a gate electrode at a turn-off time and simultaneously improves a current density by narrowing a cell pitch. The semiconductor device includes a gate electrode embedded into a trench penetrating a base region. The gate electrode is disposed into a lattice shape in a planar view, and a protective diffusion layer is formed in a drift layer at the portion underlying thereof. At least one of blocks divided by the gate electrode is a protective contact region on which the trench is entirely formed. A protective contact for connecting the protective diffusion layer at a bottom portion of the trench and a source electrode is disposed on the protective contact region.

Abstract: An insulated gate silicon carbide semiconductor device includes: a drift layer of a first conductivity type on a silicon carbide substrate of 4H type with a {0001} plane having an off-angle of more than 0° as a main surface; a first base region; a source region; a trench; a gate insulating film; a protective diffusion layer; and a second base region. The trench sidewall surface in contact with the second base region is a surface having a trench off-angle of more than 0° in a <0001> direction with respect to a plane parallel to the <0001> direction. The insulated gate silicon carbide semiconductor device can relieve an electric field of a gate insulating film and suppress an increase in on-resistance and provide a method for manufacturing the same.

Abstract: It is an object of the present invention to provide a silicon carbide semiconductor device that reduces an influence of an off-angle of a silicon carbide substrate on characteristics of the semiconductor device and achieves improved operational stability and reduced resistance. In a trench-gate silicon carbide MOSFET semiconductor device formed on the silicon carbide semiconductor substrate having the off-angle, a low-channel doped region is provided on a first sidewall surface side of the trench in a well region, and a high-channel doped region having an effective acceptor concentration lower than that of the low-channel doped region is provided on a second sidewall surface side of the trench in the well region.

Abstract: A silicon carbide semiconductor device includes trenches formed in a lattice shape on the surface of a silicon carbide substrate on which a semiconductor layer is formed, and gate electrodes formed inside of the trenches via a gate insulating film. The depth of the trenches is smaller in a portion where the trenches are crossingly formed than in a portion where the trenches are formed in parallel to each other. Consequently, the silicon carbide semiconductor device is obtained that increases a withstand voltage between the gate electrodes and corresponding drain electrodes on the semiconductor device rear surface to prevent dielectric breakdown and, at the same time, has a large area of the gate electrodes, high channel density per unit area, and low ON resistance.

Abstract: A silicon-carbide semiconductor device that relaxes field intensity in a gate insulating film, and that has a low ON-resistance. The silicon-carbide semiconductor device includes: an n-type silicon-carbide substrate; a drift layer formed on a topside of the n-type silicon-carbide substrate; a trench formed in the drift layer and that includes therein a gate insulating film and a gate electrode; a p-type high-concentration well region formed parallel to the trench with a spacing therefrom and that has a depth larger than that of the trench; and a p-type body region formed to have a depth that gradually increases when nearing from a position upward from the bottom end of the trench by approximately the thickness of the gate insulating film at the bottom of the trench toward the lower end of the p-type high-concentration well region.

Abstract: A silicon carbide semiconductor device including an SBD measuring a temperature of a silicon carbide semiconductor element. The silicon carbide semiconductor device includes a MOSFET formed on a silicon carbide epitaxial substrate, and an SBD section measuring a temperature of the MOSFET. The SBD section includes an n-type cathode region in a surface portion of a silicon carbide drift layer; an anode titanium electrode formed on the cathode region, the electrode serving as a Schottky electrode; an n-type cathode contact region of a higher concentration than that of the cathode region, formed in the surface portion of the silicon carbide drift layer to make contact with the cathode region; a cathode ohmic electrode formed on the cathode contact region; and a first p-type well region formed within the silicon carbide drift layer to surround peripheries of the cathode region and the cathode contact region.

Abstract: A source region of a MOSFET includes: a source contact region connected to a source pad; a source extension region adjacent to a channel region in a well region; and a source resistance control region arranged between the source extension region and the source contact region. The source resistance control region is different in an impurity concentration from the source extension region and the source contact region. These three regions are connected in series between the source pad and the channel region in the well region.

Abstract: A power semiconductor device includes a second conductive type sense outer-peripheral well formed to surround a plurality of sense wells on the surface of a drift layer, a first conductive type main-cell source region selectively formed on the surface of the main cell well, a first conductive type sense source region selectively formed on the surface of the sense well, a first conductive type capacitor lower electrode region selectively formed on the surface of the sense outer-peripheral well, a gate insulation film formed on the channel regions and on the sense outer-peripheral well, a gate electrode formed on the gate insulation film, and a sense pad electrically connected to the sense well and the sense source region as well as on the sense outer-peripheral well and the capacitor lower electrode region.

Abstract: A power semiconductor device includes a second conductive type sense outer-peripheral well formed to surround a plurality of sense wells on the surface of a drift layer, a first conductive type main-cell source region selectively formed on the surface of the main cell well, a first conductive type sense source region selectively formed on the surface of the sense well, a first conductive type capacitor lower electrode region selectively formed on the surface of the sense outer-peripheral well, a gate insulation film formed on the channel regions and on the sense outer-peripheral well, a gate electrode formed on the gate insulation film, and a sense pad electrically connected to the sense well and the sense source region as well as on the sense outer-peripheral well and the capacitor lower electrode region.

Abstract: A RESURF layer including a plurality of P-type implantation layers having a low concentration of P-type impurity is formed adjacent to an active region. The RESURF layer includes a first RESURF layer, a second RESURF layer, a third RESURF layer, a fourth RESURF layer, and a fifth RESURF layer that are arranged sequentially from the P-type base side so as to surround the P-type base. The second RESURF layer is configured with small regions having an implantation amount equal to that of the first RESURF layer and small regions having an implantation amount equal to that of the third RESURF layer being alternately arranged in multiple. The fourth RESURF layer is configured with small regions having an implantation amount equal to that of the third RESURF layer and small regions having an implantation amount equal to that of the fifth RESURF layer being alternately arranged in multiple.

Abstract: A silicon carbide semiconductor device including an SBD measuring a temperature of a silicon carbide semiconductor element. The silicon carbide semiconductor device includes a MOSFET formed on a silicon carbide epitaxial substrate, and an SBD section measuring a temperature of the MOSFET. The SBD section includes an n-type cathode region in a surface portion of a silicon carbide drift layer; an anode titanium electrode formed on the cathode region, the electrode serving as a Schottky electrode; an n-type cathode contact region of a higher concentration than that of the cathode region, formed in the surface portion of the silicon carbide drift layer to make contact with the cathode region; a cathode ohmic electrode formed on the cathode contact region; and a first p-type well region formed within the silicon carbide drift layer to surround peripheries of the cathode region and the cathode contact region.