Abstract: In one embodiment, a semiconductor device includes an isolated trench-electrode structure. The semiconductor device is formed using a modified photolithographic process to produce alternating regions of thick and thin dielectric layers that separate the trench electrode from regions of the semiconductor device. The thin dielectric layers can be configured to control the formation channel regions, and the thick dielectric layers can be configured to reduce switching losses.

Abstract: Source zones of a first conductivity type and body zones of a second conductivity type are formed in a semiconductor die. The source zones directly adjoin a first surface of the semiconductor die. A dielectric layer adjoins the first surface. Polysilicon plugs extend through the dielectric layer and are electrically connected to the source and the body zones. An impurity source containing at least one metallic recombination element is provided in contact with deposited polycrystalline silicon material forming the polysilicon plugs and distant to the semiconductor die. Atoms of the metallic recombination element, for example platinum atoms, may be diffused out from the impurity source into the semiconductor die to reliably reduce the reverse recovery charge.

Abstract: A termination structure for a semiconductor device includes an array of termination cells formed using a thin epitaxial layer (nanotube) formed on sidewalls of dielectric-filled trenches. In other embodiments, semiconductor devices are formed using a thin epitaxial layer (nanotube) formed on sidewalls of dielectric-filled trenches.

Abstract: According to one embodiment, a semiconductor device includes a first semiconductor region, a second semiconductor region, a third semiconductor region, a control electrode, a first main electrode, an internal electrode, and an insulating region. The control electrode is provided inside a trench. The first main electrode is in conduction with the third semiconductor region. The internal electrode is provided in the trench and in conduction with the first main electrode. The insulating region is provided between an inner wall of the trench and the internal electrode. The internal electrode includes a first internal electrode part included in a first region of the trench and a second internal electrode part included in a second region between the first region and the first main electrode. A spacing between the first internal electrode part and the inner wall is wider than a spacing between the second internal electrode part and the inner wall.

Abstract: A method for manufacturing a vertical trench IGBT includes: forming a body layer of a second conductivity type on a semiconductor substrate of a first conductivity type; forming a trench passing through the body layer; forming a trench gate in the trench via a gate insulating film; forming a polysilicon film containing an impurity of a first conductivity type on the body layer; diffusing the impurity from the polysilicon film into the body layer to form an emitter layer of a first conductivity type on the body layer; and forming a collector layer of a second conductivity type on a lower surface of the semiconductor substrate.

Abstract: A cell field has an edge and a center, an individual device cells are connected in parallel. A first type of device cells has a body region with a first size and a source region with a second size implemented in the body region, and a second type of device cells has a body region of the first size and in which a source region is omitted or the source region is smaller than the second size. The cell field includes non-overlapping cell regions, each including the same plurality of device cells. At least one sequence of cell regions is arranged between the edge and center of the cell field in which the frequency of device cells of the second type monotonically increases from cell region to cell region in the direction of the center, and one cell region of the sequence of cell regions includes or adjoins the center.

Abstract: A lateral insulated-gate bipolar transistor includes a buried insulation layer which opens only part of the collector ion implantation region and isolates the other regions, thereby reducing the loss by the turn-off time. The lateral insulated-gate bipolar transistor further includes a deep ion implantation region formed to face towards the open part of the collector ion implantation region, thereby decreasing the hole current injected into a base region under an emitter ion implantation region, and thereby greatly increasing the latch-up current level by relatively increasing the hole current injected into the deep ion implantation region having no latch-up effect.

Abstract: A semiconductor device includes a semiconductor substrate which functions as an n? drift layer, a trench IGBT formed in the front surface, an interlayer insulator film, and a metal electrode layer on the interlayer insulator film. There is a contact hole in the interlayer insulating film which has a first opening formed on the metal electrode layer side and a second opening on the semiconductor substrate side. Width w1 of the first opening on the metal electrode layer side is wider than width w2 of first opening on the semiconductor substrate side, in a direction perpendicular to the extending direction of the trench in the planar pattern of trenches. The metal electrode layer is connected to a p-type channel region and an n+ source region via the contact hole. The method of manufacturing improves the reliability of the device.

Abstract: In some embodiments, an insulated gate bipolar transistor includes a drift layer, insulation gates formed at a principle surface portion of the drift layer, base regions formed in a between-gate region, an emitter region formed in the base region so as to be adjacent to the insulation gate, an emitter electrode connected to the emitter region, a collector layer formed at the other side of the principle surface portion of the drift layer, and a collector electrode connected to the collector layer. The conductive type base regions are separated with each other by the drift layers, and the drift layer and the emitter electrode are insulated by an interlayer insulation film.

Abstract: A semiconductor device includes: a semiconductor substrate having a first semiconductor layer and a second semiconductor layer formed on a first surface; a diode having a first electrode and a second electrode; a control pad; a control electrode electrically coupled with the control pad; and an insulation member. The first electrode is formed on a second surface of the first semiconductor layer. The second electrode is formed on the first surface. Current flows between the first electrode and the second electrode. The control pad is arranged on the first surface so that the pad inputs a control signal for controlling an injection amount of a carrier into the first semiconductor layer. The insulation member insulates between the control electrode and the second electrode and between the control electrode and the semiconductor substrate.

Abstract: A semiconductor device includes: a semiconductor substrate, the semiconductor substrate comprising; an n type drift layer, a p type body layer on an upper surface side of the drift layer, and a high impurity n layer on a lower surface side of the drift layer. The high impurity n layer includes hydrogen ion donors as a dopant, and has a higher density of n type impurities than the drift layer. A lifetime control region including crystal defects as a lifetime killer is formed in the high impurity n layer and a part of the drift layer. A donor peak position is adjacent or identical to a defect peak position, at which a crystal defect density is highest in the lifetime control region in the depth direction of the semiconductor substrate. The crystal defect density in the defect peak position of the lifetime control region is 1×1012 atoms/cm3 or more.

Abstract: According to an embodiment, a trench structure and a second semiconductor layer are provided in a semiconductor device. In the trench structure, a trench is provided in a surface of a device termination portion with a first semiconductor layer of a first conductive type including a device portion and the device termination portion, and an insulator is buried in the trench in such a manner to cover the trench. The second semiconductor layer, which is of a second conductive type, is provided on the surface of the first semiconductor layer, is in contact with at least a side on the device portion of the trench, and has a smaller depth than the trench. The insulator and a top passivation film for the semiconductor device are made of the same material.

Abstract: In one embodiment, a power transistor device comprises a substrate that forms a PN junction with an overlying buffer layer. The power transistor device further includes a first region, a drift region that adjoins a top surface of the buffer layer, and a body region. The body region separates the first region from the drift region. First and second dielectric regions respectively adjoin opposing lateral sidewall portions of the drift region. The dielectric regions extend in a vertical direction from at least just beneath the body region down at least into the buffer layer. First and second field plates are respectively disposed in the first and second dielectric regions. A trench gate that controls forward conduction is disposed above the dielectric region adjacent to and insulated from the body region.

Abstract: A semiconductor device includes a semiconductor diode. The semiconductor diode includes a drift region and a first semiconductor region of a first conductivity type formed in or on the drift region. The first semiconductor region is electrically coupled to a first terminal via a first surface of a semiconductor body. The semiconductor diode includes a channel region of a second conductivity type electrically coupled to the first terminal, wherein a bottom of the channel region adjoins the first semiconductor region. A first side of the channel region adjoins the first semiconductor region.

Abstract: According to one embodiment, a semiconductor device includes: a drain layer; a drift layer formed on the drain layer, an effective impurity concentration of the drift layer being lower than an effective impurity concentration of the drain layer; a base layer formed on the drift layer; a source layer selectively formed on the base layer; a gate insulating film formed on inner surfaces of trenches, the trenches piercing the base layer from an upper surface of the source layer; a gate electrode filled into an interior of the trench; an inter-layer insulating film formed on the trench to cover an upper surface of the gate electrode, at least an upper surface of the inter-layer insulating film being positioned higher than the upper surface of the source layer; and a contact mask. The contact mask is formed on the inter-layer insulating film, and is conductive or insulative.

Abstract: A power semiconductor device with improved avalanche capability structures is disclosed. By forming at least an avalanche capability enhancement doped regions with opposite conductivity type to epitaxial layer underneath an ohmic contact doped region which surrounds at least bottom of trenched contact filled with metal plug between two adjacent gate trenches, avalanche current is enhanced with the disclosed structures.

Abstract: A semiconductor device includes a stripe-shaped gate trench formed in one major surface of n-type drift layer, a gate trench including gate polysilicon formed therein, and a gate polysilicon connected to a gate electrode. A p-type base layer is formed selectively in mesa region between adjacent gate trenches and a p-type base layer including an n-type emitter layer and connected to emitter electrode. One or more dummy trenches are formed between p-type base layers adjoining to each other in the extending direction of gate trenches. An electrically conductive dummy polysilicon is formed on an inner side wall of dummy trench with a gate oxide film interposed between the dummy polysilicon and dummy trench. The dummy polysilicon is spaced apart from the gate polysilicon and may be connected to the emitter electrode.

Abstract: Super-junction MOSFETs by trench fill system requires void-free filling epitaxial growth. This may require alignment of plane orientations of trenches in a given direction. Particularly, when column layout at chip corner part is bilaterally asymmetrical with a diagonal line between chip corners, equipotential lines in a blocking state are curved at corner parts due to column asymmetry at chip corner. This tends to cause points where equipotential lines become dense, which may cause breakdown voltage reduction. In the present invention, in power type semiconductor active elements such as power MOSFETs, a ring-shaped field plate is disposed in chip peripheral regions around an active cell region, etc., assuming a nearly rectangular shape. The field plate has an ohmic-contact part in at least a part of the portion along the side of the rectangle. However, in the portion corresponding to the corner part of the rectangle, an ohmic-contact part is not disposed.

Abstract: An insulated gate semiconductor device, comprising: a semiconductor body having a front side and a back side opposite to one another; a drift region, which extends in the semiconductor body and has a first type of conductivity and a first doping value; a body region having a second type of conductivity, which extends in the drift region facing the front side of the semiconductor body; a source region, which extends in the body region and has the first type of conductivity; and a buried region having the second type of conductivity, which extends in the drift region at a distance from the body region and at least partially aligned to the body region in a direction orthogonal to the front side and to the back side.

Abstract: A termination structure for a semiconductor device includes an array of termination cells formed using a thin epitaxial layer (nanotube) formed on sidewalls of dielectric-filled trenches. In other embodiments, semiconductor devices are formed using a thin epitaxial layer (nanotube) formed on sidewalls of dielectric-filled trenches.

Abstract: A semiconductor apparatus includes a substrate having a device region and a peripheral region located around the device region. A first semiconductor region is formed within the device region, is of a first conductivity type, and is exposed at an upper surface of the substrate. Second-fourth semiconductor regions are formed within the peripheral region. The second semiconductor region is of the first conductivity type, has a lower concentration of the first conductivity type of impurities, is exposed at the upper surface, and is consecutive with the first semiconductor region directly or indirectly. The third semiconductor region is of a second conductivity type, is in contact with the second semiconductor region from an underside, and is an epitaxial layer. The fourth semiconductor region is of the second conductivity type, has a lower concentration of the second conductivity type of impurities, and is in contact with the third semiconductor region from an underside.

Abstract: A semiconductor device includes a first trench and a second trench extending into a semiconductor body from a surface. A body region of a first conductivity type adjoins a first sidewall of the first trench and a first sidewall of the second trench, the body region including a channel portion adjoining to a source structure and being configured to be controlled in its conductivity by a gate structure. The channel portion is formed at the first sidewall of the second trench and is not formed at the first sidewall of the first trench. An electrically floating semiconductor zone of the first conductivity type adjoins the first trench and has a bottom side located deeper within the semiconductor body than the bottom side of the body region.

Abstract: A semiconductor device includes a first-conductivity-type semiconductor layer including an active region in which a transistor having impurity regions is formed and a marginal region surrounding the active region, a second-conductivity-type channel layer formed between the active region and the marginal region and forming a front surface of the semiconductor layer, at least one gate trench formed in the active region to extend from the front surface of the semiconductor layer through the channel layer, a gate insulation film formed on an inner surface of the gate trench, a gate electrode formed inside the gate insulation film in the gate trench, and at least one isolation trench arranged between the active region and the marginal region to surround the active region and extending from the front surface of the semiconductor layer through the channel layer, the isolation trench having a depth equal to that of the gate trench.

Abstract: The present invention provides a high-voltage semiconductor device including a deep well, a first doped region disposed in the deep well, a high-voltage well, a second doped region disposed in the high-voltage well, a first gate structure disposed on the high-voltage well between the second doped region and the first doped region, a doped channel region disposed in the high-voltage region and in contact with the second doped region and the deep well, and a third doped region disposed in the high-voltage well. The high-voltage well has a first conductive type, and the deep well, the first doped region, the second doped region, the doped channel region, and the third doped region have a second conductive type different from the first conductive type.

Abstract: A vertical and trench type insulated gate MOS semiconductor device includes a plurality of regions each being provided between adjacent ones of a plurality of the straight-line-like trenches arranged in parallel and forming a surface pattern of a plurality of straight lines. A plurality of first inter-trench surface regions are provided, each with an n+-type emitter region and a p+-type body region formed thereon, and the surfaces of regions are alternately arranged along the trench in the longitudinal direction thereof with an emitter electrode being in common contact with both of the surfaces of the n+-type emitter region and the p+-type body region. A plurality of second inter-trench surface regions are provided each of which is formed along the trench in the longitudinal direction thereof with one of the surface of the p base region and the surface of the n-type semiconductor substrate.

Abstract: The invention of the present application provides an IE-type trench IGBT. In the IE-type trench IGBT, each of linear unit cell areas that configure a cell area is comprised principally of linear active and inactive cell areas. The linear active cell area is divided into an active section having an emitter region and an inactive section as seen in its longitudinal direction.

Abstract: Provided is a manufacturing method for an insulated-gate bipolar transistor (IGBT). The manufacturing method includes providing a structure including a substrate, a first conductivity type epitaxial layer formed on the substrate, a gate electrode formed on a first surface of the epitaxial layer, a second conductivity type body region formed at opposite sides of the gate electrode in the first surface of the epitaxial layer, and a first conductivity type source region formed within the body region; removing a portion of the substrate by back grinding; and removing the other portion of the substrate by etching until the second surface of the epitaxial layer is exposed.

Abstract: A semiconductor device includes a first semiconductor layer and a second semiconductor layer of opposite conductivity type, a first epitaxial layer of the first conductivity type formed on sidewalls of the trenches, and a second epitaxial layer of the second conductivity type formed on the first epitaxial layer where the second epitaxial layer is electrically connected to the second semiconductor layer. The first epitaxial layer and the second epitaxial layer form parallel doped regions along the sidewalls of the trenches, each having uniform doping concentration. The second epitaxial layer has a first thickness and a first doping concentration and the first epitaxial layer and a mesa of the first semiconductor layer together having a second thickness and a second average doping concentration where the first and second thicknesses and the first doping concentration and second average doping concentrations are selected to achieve charge balance in operation.

Abstract: In a manufacturing method of a semiconductor device, a trench is defined in a semiconductor substrate, and an adjuster layer having a first conductivity type impurity concentration higher than a drift layer is formed at a portion of the semiconductor substrate adjacent to a bottom wall of the trench. A channel layer is formed by introducing second conductivity type impurities to a portion of the semiconductor substrate adjacent to a sidewall of the trench and between the adjustment layer and a main surface of the semiconductor substrate while restricting the channel layer from extending in a depth direction of the trench by the adjustment layer.

Abstract: Silicon carbide semiconductor device includes trench, in which connecting trench section is connected to straight trench section. Straight trench section includes first straight trench and second straight trench extending in parallel to each other. Connecting trench section includes first connecting trench perpendicular to straight trench section, second connecting trench that connects first straight trench and first connecting trench to each other, and third connecting trench that connects second straight trench and first connecting trench to each other. Second connecting trench extends at 30 degrees of angle with the extension of first straight trench. Third connecting trench extends at 30 degrees of angle with the extension of second straight trench. A manufacturing method according to the invention for manufacturing a silicon carbide semiconductor device facilitates preventing defects from being causes in a silicon carbide semiconductor device during the manufacture thereof.

Abstract: A power semiconductor device includes a first semiconductor layer of a first conduction type, a second semiconductor layer of the first conduction type, a third semiconductor layer of a second conduction type, a fourth semiconductor layer of the first conduction type, a gate insulating film, a gate electrode, an interlayer insulating film, a fifth semiconductor layer of the second conduction type, a sixth semiconductor layer of the second conduction type, an insulative current narrowing body, a first electrode, and a second electrode. The sixth semiconductor layer of the second conduction type contains a second conduction type impurity in a concentration higher than a second conduction type impurity concentration of the fifth semiconductor layer. The insulative current narrowing body is provided in the fifth semiconductor layer. The insulative current narrowing body has a surface parallel to the surface of the fifth semiconductor layer and a space provided in the surface.

Abstract: A power semiconductor device with improved avalanche capability structures is disclosed. By forming at least an avalanche capability enhancement doped regions with opposite conductivity type to epitaxial layer underneath an ohmic contact doped region which surrounds at least bottom of trenched contact filled with metal plug between two adjacent gate trenches, avalanche current is enhanced with the disclosed structures.

Abstract: Disclosed is a semiconductor component that includes a semiconductor body, a first emitter region of a first conductivity type in the semiconductor body, a second emitter region of a second conductivity type spaced apart from the first emitter region in a vertical direction of the semiconductor body, a base region of one conductivity type arranged between the first emitter region and the second emitter region, and at least two higher doped regions of the same conductivity type as the base region and arranged in the base region. The at least two higher doped regions are spaced apart from one another in a lateral direction of the semiconductor body and separated from one another only by sections of the base region.

Abstract: A semiconductor device having a semiconductor body, a source metallization arranged on a first surface of the semiconductor body and a trench including a first trench portion and a second trench portion and extending from the first surface into the semiconductor body is provided. The semiconductor body further includes a pn-junction formed between a first semiconductor region and a second semiconductor region. The first trench portion includes an insulated gate electrode which is connected to the source metallization, and the second trench portion includes a conductive plug which is connected to the source metallization and to the second semiconductor region.

Abstract: An IGBT with a fast reverse recovery time rectifier includes an N-type drift epitaxial layer, a gate, a gate insulating layer, a P-type doped base region, an N-type doped source region, a P-type doped contact region, and a P-type lightly doped region. The P-type doped base region is disposed in the N-type drift epitaxial layer, and the P-type doped contact region is disposed in the N-type drift epitaxial layer. The P-type lightly doped region is disposed between the P-type contact doped region and the N-type drift epitaxial layer, and is in contact with the N-type drift epitaxial layer.

Abstract: A semiconductor device includes a semiconductor substrate having a first surface and a second surface. A main region and a sensing region are formed on the first surface side of the semiconductor substrate. A RC-IGBT is formed in the main region and a sensing element for passing electric currents proportional to electric currents flowing through the RC-IGBT is formed in the sensing region. A collector region and a cathode region of the sensing element are formed on the second surface side of the semiconductor substrate. The collector region is located directly below the sensing region in a thickness direction of the semiconductor substrate. The cathode region is not located directly below the sensing region in the thickness direction.

Abstract: A conventional semiconductor device has a problem that, when a vertical PNP transistor as a power semiconductor element is used in a saturation region, a leakage current into a substrate is generated. In a semiconductor device of the present invention, two P type diffusion layers as a collector region are formed around an N type diffusion layer as a base region. One of the P type diffusion layers is formed to have a lower impurity concentration and a narrower diffusion width than the other P type diffusion layer. In this structure, when a vertical PNP transistor is turned on, a region where the former P type diffusion layer is formed mainly serves as a parasite current path. Thus, a parasitic transistor constituted of a substrate, an N type buried layer and a P type buried layer is prevented from turning on, and a leakage current into the substrate is prevented.

Abstract: A semiconductor package may comprise a semiconductor substrate, a MOSFET device having a plurality cells formed on the substrate, and a source region common to all cells disposed on a bottom of the substrate. Each cell comprises a drain region on a top of the semiconductor device, a gate to control a flow of electrical current between the source and drain regions, a source contact proximate the gate; and an electrical connection between the source contact and source region. At least one drain connection is electrically coupled to the drain region. Source, drain and gate pads are electrically connected to the source region, drain region and gates of the devices. The drain, source and gate pads are formed on one surface of the semiconductor package. The cells are distributed across the substrate, whereby the electrical connections between the source contact of each device and the source region are distributed across the substrate.

Abstract: A semiconductor device includes first semiconductor layer of a first conductivity type; a second semiconductor layer of a second conductivity type that is formed near a surface of the first semiconductor layer; a first main electrode that is electrically connected to the second semiconductor layer; a third semiconductor layer of the second conductivity type that neighbors the first semiconductor layer; a fourth semiconductor layer of the first conductivity type that is selectively disposed in an upper portion of the third semiconductor layer; a second main electrode that is electrically connected to the third semiconductor layer and the fourth semiconductor layer; a trench whose side face is in contact with the third semiconductor layer and the fourth semiconductor layer; a gate electrode that is formed along the side face of the trench by a sidewall of polysilicon; and a polysilicon electrode.

Abstract: Transistor devices can be fabricated with an integrated diode using a self-alignment. The device includes a doped semiconductor substrate having one or more electrically insulated gate electrodes formed in trenches in the substrate. One or more body regions are formed in a top portion of the substrate proximate each gate trench. One or more source regions are formed in a self-aligned fashion in a top portion of the body regions proximate each gate trench. One or more thick insulator portions are formed over the gate electrodes on a top surface of the substrate with spaces between adjacent thick insulator portions. A metal is formed on top of the substrate over the thick insulator portions. The metal forms a self-aligned contact to the substrate through the spaces between the thick insulator portions. An integrated diode is formed under the self-aligned contact.

Abstract: A semiconductor device (100) including a cell region and a peripheral region around the cell region, the cell region including: a first semiconductor layer (1) having a first conductivity type; a second semiconductor layer (2) which is formed in an island shape on the surface of the first semiconductor layer and has a second conductivity type different from the first conductivity type; a third semiconductor layer (3) which is formed in an island shape on the surface of the second semiconductor layer and has the first conductivity type; and a plurality of gate trenches (11) penetrating the second and third semiconductor layer and reaching the inside of the first semiconductor layer, and the peripheral region including: a plurality of peripheral trenches (14) penetrating the second and third semiconductor layers and reaching the inside of the first semiconductor layer; and a termination layer (6) which is formed in an island shape in the surface of the first semiconductor layer and has the first conductivity ty

Abstract: There is provided a semiconductor device in which an amount of fluctuations in output capacitance and feedback capacitance is reduced. In a trench-type insulated gate semiconductor device, a width of a portion of an electric charge storage layer in a direction along which a gate electrode and a dummy gate are aligned is set to be at most 1.4 ?m.

Abstract: This invention discloses an insulated gate bipolar transistor (IGBT) device formed in a semiconductor substrate. The IGBT device has a split-shielded trench gate that includes an upper gate segment and a lower shield segment. The IGBT device may further include a dummy trench filled with a dielectric layer disposed at a distance away from the split-shielded trench gate. The IGBT device further includes a body region extended between the split-shielded trench gate and the dummy trench encompassing a source region surrounding the split-shielded trench gate near a top surface of the semiconductor substrate. The IGBT device further includes a heavily doped N region disposed below the body region and above a source-dopant drift region above a bottom body-dopant collector region at a bottom surface of the semiconductor substrate. In an alternative embodiment, the IGBT may include a planar gate with a trench shield electrode.

Abstract: A vertical semiconductor device (e.g. a vertical power device, an IGBT device, a vertical bipolar transistor, a UMOS device or a GTO thyristor) is formed with an active semiconductor region, within which a plurality of semiconductor structures have been fabricated to form an active device, and below which at least a portion of a substrate material has been removed to isolate the active device, to expose at least one of the semiconductor structures for bottom side electrical connection and to enhance thermal dissipation. At least one of the semiconductor structures is preferably contacted by an electrode at the bottom side of the active semiconductor region.

Abstract: According to an embodiment, a semiconductor device includes a second semiconductor layer provided on a first semiconductor layer and including first pillars and second pillars. A first control electrode is provided in a trench of the second semiconductor layer and a second control electrode is provided on the second semiconductor layer and connected to the first control electrode. A first semiconductor region is provided on a surface of the second semiconductor layer except for a portion under the second control electrode. A second semiconductor region is provided on a surface of the first semiconductor region, the second semiconductor region being apart from the portion under the second control electrode and a third semiconductor region is provided on the first semiconductor region. A first major electrode is connected electrically to the first semiconductor layer and a second major electrode is connected electrically to the second and the third semiconductor region.

Abstract: A carrier is prevented from being stored in a guard ring region in a semiconductor device. The semiconductor device has an IGBT cell including a base region and an emitter region formed in an n? type drift layer, and a p type collector layer arranged under the drift layer with a buffer layer interposed therebetween. A guard ring region having a guard ring is arranged around the IGBT cell. A lower surface of the guard ring region has a mesa structure provided by removing the collector layer.

Abstract: A semiconductor device includes a base layer, a second conductivity type semiconductor layer, a first insulating film, and a first electrode. The first insulating film is provided on an inner wall of a plurality of first trenches extending from a surface of the second conductivity type semiconductor layer toward the base layer side, but not reaching the base layer. The first electrode is provided in the first trench via the first insulating film, and provided in contact with a surface of the second conductivity type semiconductor layer. The second conductivity type semiconductor layer includes first and second regions. The first region is provided between the first trenches. The second region is provided between the first second conductivity type region and the base layer, and between a bottom part of the first trench and the base layer. The second region has less second conductivity type impurities than the first region.

Abstract: In one embodiment, a power transistor device comprises a substrate that forms a PN junction with an overlying buffer layer. The power transistor device further includes a first region, a drift region that adjoins a top surface of the buffer layer, and a body region. The body region separates the first region from the drift region. First and second dielectric regions respectively adjoin opposing lateral sidewall portions of the drift region. The dielectric regions extend in a vertical direction from at least just beneath the body region down at least into the buffer layer. First and second field plates are respectively disposed in the first and second dielectric regions. A trench gate that controls forward conduction is disposed above the dielectric region adjacent to and insulated from the body region.

Abstract: According to one embodiment, a semiconductor device includes a first conductivity type base layer, a second conductivity type base layer, a gate insulating film, a first conductivity type source layer, a gate electrode, and a main electrode. The gate electrode is provided inside of the gate insulating film in the trench. The main electrode is provided on the surface of the second conductivity type base layer and on a surface of the first conductivity type source layer. The main electrode is provided at a position deeper than the gate electrode and the second conductivity type base layer in the trench. The main electrode is electrically connected to the second conductivity type base layer and the first conductivity type source layer.

Abstract: According to one embodiment, a semiconductor device includes a first major electrode, a first semiconductor layer, a first conductivity-type base layer, a second conductivity-type base layer, a second semiconductor layer, a buried layer, a buried electrode, a gate insulating film, a gate electrode, and a second major electrode. The buried layer of the second conductivity type selectively is provided in the first conductivity-type base layer. The buried electrode is provided in a bottom portion of a trench which penetrates the second conductivity-type base layer to reach the buried layer. The buried electrode is in contact with the buried layer. The gate electrode is provided inside the gate insulating film in the trench. The second major electrode is provided on the second semiconductor layer and is electrically connected to the second semiconductor layer and the buried electrode.