Abstract: A method of forming a charge balance MOSFET includes the following steps. A substrate with an overlying epitaxial layer both of a first conductivity type, are provided. A gate trench extending through the epitaxial layer and terminating within the substrate is formed. A shield dielectric lining sidewalls and bottom surface of the gate trench is formed. A shield electrode is formed in the gate trench. A gate dielectric layer is formed along upper sidewalls of the gate trench. A gate electrode is formed in the gate trench such that the gate electrode extends over but is insulated from the shield electrode. A deep dimple extending through the epitaxial layer and terminating within the substrate is formed such that the deep dimple is laterally spaced from the gate trench. The deep dimple is filled with silicon material of the second conductivity type.

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 method for fabricating a semiconductor device includes etching a substrate to form a first recess having a micro trench, etching the substrate disposed under the first recess to form a second recess having a profile substantially vertical and a width greater than a portion of the first recess where no micro trench is formed, etching the substrate disposed under the second recess to form a third recess having a profile substantially spherical, and forming a gate pattern over a resultant recess including the first to third recesses.

Abstract: A semiconductor apparatus includes a cell section including at least two transistors. A layer interval insulation coat is formed at least overlying the gate electrode use polysilicon and the gate contact use polysilicon. A source electrode metal coat is formed overlying the semiconductor substrate and insulated from the gate electrode use polysilicon and the gate contact use polysilicon, and is electrically connected to the body diffusion layer and the source diffusion layer. A gate use connection hole is formed on the layer interval insulation coat overlying the gate contact use polysilicon. The gate use connection hole has a width larger than that of the trench. A gate electrode metal coat is formed on the gate use connection hole and the layer interval insulation coat. The polysilicon coat is formed at the same level or lower than the surface of the semiconductor substrate.

Abstract: A semiconductor component has a semiconductor body in which a trench structure is provided. An electrode structure embedded in the trench structure is at least partly insulated from its surroundings by an insulation structure, and is contact-connected in a contact-connecting region via a contact hole that penetrates through an upper region of the insulation structure. The semiconductor component has at least two trenches running next to one another, at least one of said trenches containing a part of the electrode structure. The trenches are oriented so that at least the regions of the insulation structure which are provided in the upper region of the trenches overlap one another in an overlap region. The contact hole is arranged above the at least two trenches in such a way that at least parts of the overlap region and at least one of the electrode structure parts are contact-connected via the contact hole.

Abstract: The present invention relates to a technique for reducing the on-voltage of the semiconductor device by increasing the concentration of minority carriers in the deep region (26) and the intermediate region (28). A semiconductor device according to the invention comprises an electrode, a top region (36) of a second conductivity type connected to the electrode, a deep region of the second conductivity type, and an intermediate region of a first conductivity type connected to the electrode. A portion of the intermediate region isolates the top region and the deep region. The semiconductor device further comprises a gate electrode (32) facing the portion of the intermediate region via an insulating layer. The portion facing the gate electrode isolates the top region and the deep region. The semiconductor device according to the invention further comprises a barrier region (40) that is formed within the intermediate region and/or the top region.

Abstract: A semiconductor device includes: a semiconductor layer, a first semiconductor region provided on a major surface of the semiconductor layer, a second semiconductor region provided in a surface portion of the first semiconductor region, a trench extending through the second semiconductor region and the first semiconductor region to the semiconductor layer, a first insulating film provided on an inner wall of the trench, a third semiconductor region filling the trench below an interface between the semiconductor layer and the first semiconductor region, a second insulating film provided on the third semiconductor region, a gate electrode filling the trench above the second insulating film. A portion of the first insulating film in contact with the semiconductor layer is opened. The semiconductor layer is in contact with the third semiconductor region through the opened portion.

Abstract: The present invention provides a semiconductor device (20) comprising a trench (5) formed in a semiconductor substrate formed of a stack (4) of layers (1,2,3), a layer (6) of a first, grown dielectric material covering sidewalls and bottom of the trench (5), the layer (6) including one or more notches (13) at the bottom of the trench (5) and one or more spacers (14) formed of a second, deposited dielectric material to fill the one or more notches (13) in the layer (6) formed of the first, grown dielectric material. The semiconductor device (20) according to the present invention shows improved breakdown voltage and on-resistance. The present invention furthermore provides a method for the manufacturing of such semiconductor devices (20).

Abstract: A semiconductor component and method of making a semiconductor component is disclosed. In one embodiment, the semiconductor component includes a drift region of a first conductivity type, a body region of a second conductivity type, and a trench extending into the body region. A semiconductor region of the first conductivity type is in contact with the drift region and the body region and is arranged at a distance from the trench.

Abstract: In an embodiment of the present invention, a Trench MOSFET includes a trench region provided on a semiconductor substrate. The semiconductor substrate includes a P-type semiconductor substrate, a P-type semiconductor epitaxial layer, an N-type semiconductor body region, and a P-type semiconductor source diffusion. The substrate, the epitaxial layer, the body region, and the source diffusion are adjacently formed in this order. A P-type semiconductor channel region formed of a SiGe layer is provided on a bottom surface and a side wall of the trench region. This facilitates carrier movement in the channel region, reducing ON resistance of the Trench MOSFET. Thus, a Trench MOSFET allowing reduction in the ON resistance without reducing a breakdown voltage is realized.

Abstract: A semiconductor device having recess gates and a method for fabricating the same. The semiconductor device includes a semiconductor substrate having inverse triangular recesses formed therein; a gate insulating film having a designated thickness formed on the semiconductor substrate; gate electrodes formed on the gate insulating film so that the gate electrodes fill the inverse triangular recesses and protrude from the surface of the semiconductor substrate; and first and second junction regions formed in the semiconductor substrate and opposed to each other so that the corresponding one of the gate electrodes is interposed therebetween.

Abstract: After an element isolation region is formed using a field-forming silicon nitride film, the silicon nitride film and a semiconductor substrate are patterned. Thereafter, the silicon nitride film and the semiconductor substrate are patterned, thereby forming a gate trench reaching the semiconductor substrate in an active region. Next, after a gate electrode is formed within a gate trench, the silicon nitride film is removed, thereby forming a contact hole. A contact plug is buried into this contact hole. Accordingly, a diffusion layer contact pattern becomes unnecessary, and the active region can be reduced. Because a gate electrode is buried in the gate trench, a gate length is increased, and a sub-threshold current can be reduced.

Abstract: A charge storage layer of first conductive type is formed on the first principal surface of a semiconductor substrate. A base layer of second conductive type is formed on the charge storage layer. Each trench formed through the base layer and the charge storage layer is lined with an insulating film and filled with a trench gate electrode. Dummy trenches are formed on both sides of each trench. Source layers of first conductive type are selectively formed in the surface of the base layer and in contact with the sidewalls of the trenches. The source layers are spaced apart from each other and arranged in the longitudinal direction of the trenches. A contact layer of second conductive type is formed in the surface of the base layer and between each two adjacent source layers arranged in the longitudinal direction of the trenches. A collector layer of second conductive type is formed on the second principal surface of the semiconductor substrate.

Abstract: Aiming at providing a semiconductor device capable of reducing the ON-resistance when voltage smaller than a predetermined value is applied to the base region and the drift region, and capable of increasing the ON-resistance so as to prevent thermal fracture when the voltage is not smaller than the predetermined value, and at providing a method of fabricating such semiconductor device, a P-type diffusion layer 7 is formed in an N-type drift region 2 of a semiconductor device 100, as being apart from a base region 5, wherein the diffusion layer 7 is formed in a region partitioned by lines L each extending from each of the intersections of the boundary B, between the drift region 2 and a base area 5A of the base region 5, and the side faces of a trench 15 surrounding the base area 5A of the base region 5, towards the bottom plane of the drift region 2 right under the base area 5A, while keeping an angle ?2 of 50° between the lines L and the boundary B.

Abstract: A semiconductor device includes: a first semiconductor layer; a second semiconductor layer on the first semiconductor layer; a third semiconductor layer on the second semiconductor layer; a fourth semiconductor layer in a part of the third semiconductor layer; a trench penetrating the fourth semiconductor layer and the third semiconductor layer and reaching the second semiconductor layer; a gate insulation film on an inner wall of the trench; a gate electrode on the gate insulation film in the trench; a first electrode; and a second electrode. The trench includes a bottom with a curved surface having a curvature radius equal to or smaller than 0.5 ?m.

Abstract: A semiconductor device includes a transistor. The transistor includes a substrate having an inclined surface, a first upper surface extending from a lower portion of the inclined surface, and a second upper surface extending from an upper end of the inclined surface. A gate stack structure is formed on the inclined surface and includes a gate electrode. A first impurity region formed on one of the first and second upper surfaces contacts the gate stack structure. A second impurity region formed on the second upper surface contacts the gate stack structure. A channel between the first and second impurity regions is formed along the inclined surface in a crystalline direction.

Abstract: A punch-through type IGBT generally has a thick p++-type collector layer. Therefore, the FWD need be externally attached to the IGBT when the IGBT is used as a switching element in an inverter circuit for driving a motor load, and thus the number of processes and components increases. In the invention, trenches are formed penetrating through a collector layer and reaching a buffer layer. A collector electrode is formed in the trenches, too. With this structure, a current path is formed between an emitter electrode and the collector electrode without through the collector layer and functions as the FWD.

Abstract: A method of fabricating a semiconductor device includes providing a semiconductor substrate in which a gate insulating layer and a pad layer are formed in an active region. A first trench is formed in an isolation region of the substrate. A passivation film is formed to cover the pad layer and fill the first trench. A second trench is formed by patterning the pad layer and removing an exposed semiconductor substrate, the second trench being formed within the first trench. An ion implantation process is performed on the semiconductor substrate exposed through the second trench.

Abstract: A vertical semiconductor power device includes a plurality of semiconductor power cells connected to a bottom electric terminal disposed on a bottom surface of a semiconductor substrate and at least a top electrical terminal disposed on a top surface of the substrate and connected to the semiconductor power cells. The top electrical terminal further includes a solderable front metal for soldering to a conductor for providing an electric connection therefrom. In an exemplary embodiment, the conductor soldering to the solderable front metal includes a conductor of a high-heat-conductivity metal plate. In another exemplary embodiment, the conductor soldering to the solderable front metal includes a copper plate. In another exemplary embodiment, the solderable front metal includes a Ti/Ni/Au front metal. In another exemplary embodiment, the solderable front metal includes a Ti/Ni/Ag front metal.

Abstract: A power semiconductor device includes a semiconductor substrate having a plurality of trenches formed in an upper surface thereof; a buried insulating film; a buried field plate electrode; a control electrode; a first main electrode provided on a lower side of the semiconductor substrate; and a second main electrode provided on an upper side of the semiconductor substrate. The semiconductor substrate includes: a first semiconductor; a second semiconductor layer of the first conductivity type and a third semiconductor layer of a second conductivity type; a fourth semiconductor layer; and a fifth semiconductor layer. The buried insulating film is thicker than a gate insulating film. At least one of the second semiconductor layer and the third semiconductor layer has a portion with its sheet dopant concentration varying along a depth direction of the semiconductor substrate.

Abstract: A shielded gate field effect transistor (FET) comprises a plurality of trenches extending into a semiconductor region. A shield electrode is disposed in a bottom portion of each trench, and a gate electrode is disposed over the shield electrode in each trench. An inter-electrode dielectric (IED) extends between the shield electrode and the gate electrode. The IED comprises a first oxide layer and a nitride layer over the first oxide layer.

Abstract: Merging together the drift regions in a low-power trench MOSFET device via a dopant implant through the bottom of the trench permits use of a very small cell pitch, resulting in a very high channel density and a uniformly doped channel and a consequent significant reduction in the channel resistance. By properly choosing the implant dose and the annealing parameters of the drift region, the channel length of the device can be closely controlled, and the channel doping may be made highly uniform. In comparison with a conventional device, the threshold voltage is reduced, the channel resistance is lowered, and the drift region on-resistance is also lowered. Implementing the merged drift regions requires incorporation of a new edge termination design, so that the PN junction formed by the P epi-layer and the N+ substrate can be terminated at the edge of the die.

Abstract: A field-effect transistor has: a substrate having a first cavity; a gate electrode buried in the substrate; and diffusion layers formed in the substrate and being in contact with the first cavity. A channel region is formed substantially perpendicular to a surface of the substrate between the diffusion layers.

Abstract: This invention discloses a semiconductor power device that includes a plurality of power transistor cells surrounded by a trench opened in a semiconductor substrate. At least one of the cells constituting an active cell has a source region disposed next to a trenched gate electrically connecting to a gate pad and surrounding the cell. The trenched gate further has a bottom-shielding electrode filled with a gate material disposed below and insulated from the trenched gate. At least one of the cells constituting a source-contacting cell surrounded by the trench with a portion functioning as a source connecting trench is filled with the gate material for electrically connecting between the bottom-shielding electrode and a source metal disposed directly on top of the source connecting trench.

Abstract: A semiconductor device has a substrate, a source region formed on the surface portion of the substrate, a first insulating layer formed on the substrate, a gate electrode formed on the first insulating layer, a second insulating layer formed on the gate electrode, a body section connected with the source region, penetrating through the first insulating layer, the gate electrode and the second insulating layer, and containing a void, a gate insulating film surrounding the body section, and formed between the body section and the gate electrode, and a drain region connected with the body section.

Abstract: A semiconductor region with an epitaxial layer extending over the semiconductor region is provided. A first silicon etch is performed to form an upper trench portion extending into and terminating within the epitaxial layer. A protective material is formed extending along sidewalls of the upper trench portion and over mesa regions adjacent the upper trench portion but not along a bottom surface of the upper trench portion. A second silicon etch is performed to form a lower trench portion extending from the bottom surface of the upper trench portion through the epitaxial layer and terminating within the semiconductor region, such that the lower trench portion is narrower than the upper trench portion.

Abstract: A method for manufacturing a semiconductor device includes forming a device isolation film by a double Shallow Trench Isolation (STI) process, forming a first active region having a negative slope and a second active region having a positive slope. Additionally, the method includes applying a recess region and a bulb-type recess region to the above-extended active region so as to prevent generation of horns in the active regions. This structure results in improvement in effective channel length and area.

Abstract: A field effect transistor includes a plurality of trenches extending into a silicon layer. Each trench has upper sidewalls that fan out. Contact openings extend into the silicon layer between adjacent trenches such that each trench and an adjacent contact opening form a common upper sidewall portion. Body regions extend between adjacent trenches, and source regions extend in the body regions adjacent opposing sidewalls of each trench. The source regions have a conductivity type opposite that of the body regions.

Abstract: A method for fabricating a recessed-gate transistor is disclosed. A trench is recessed into a substrate. A poly/nitride spacer is formed on sidewalls of the trench. A trench bottom oxide is formed. The spacer is then stripped off. A source/drain doping region is formed on the exposed sidewalls of the trench in a self-aligned fashion. The trench bottom oxide is then stripped, thereby forming a curved gate channel.

Abstract: In accordance with an embodiment of the present invention, a gate structure for a U-shape Metal-Oxide-Semiconductor (UMOS) device includes a dielectric layer formed into a U-shape having side walls and a floor to form a trench surrounding a dielectric layer interior region, a doped poly-silicon layer deposited adjacent to the dielectric layer within the dielectric layer interior region where the doped poly-silicon layer has side walls and a floor surrounding a doped poly-silicon layer interior region, a first metal layer deposited on the doped poly-silicon layer on a side opposite from the dielectric layer where the first metal layer has side walls and a floor surrounding a first metal layer interior region, and an undoped poly-silicon layer deposited to fill the first metal layer interior region.

Abstract: A gate electrode of a transistor can include an interface between a polysilicon conformal layer and a tungsten layer thereon in a trench in a substrate and a capping layer extending across the trench and covering the interface. Related methods are also disclosed.

Abstract: A trench PT IGBT (or NPT IGBT) having clamp diodes for ESD protection and prevention of shortage among gate, emitter and collector. The clamp diodes comprise multiple back-to-back Zener Diode composed of doped regions in a polysilicon layer doped with dopant ions of a first conductivity type next to a second conductivity type disposed on an insulation layer above said semiconductor power device. Trench gates are formed underneath the contact areas of the clamp diodes as the buffer layer for prevention of shortage.

Abstract: A method for forming a metal pattern in a semiconductor device includes forming an etch stop layer over a semi-finished substrate including a metal layer, forming a hard mask over the etch stop layer, etching the hard mask to form a hard mask pattern exposing the etch stop layer, and etching the etch stop layer and the metal layer using the hard mask pattern.

Abstract: A semiconductor device and method of manufacturing the same includes an n?-single crystal silicon substrate, with an oxide film selectively formed thereon. On the oxide film, gate polysilicon is formed. The surface of the gate polysilicon is covered with a gate oxide film whose surface is covered with a cathode film doped in an n-type with an impurity concentration higher than that of the substrate as an n?-drift layer. In the cathode film, a section in contact with the substrate becomes an n+-buffer region with a high impurity concentration, next to which a p-base region is formed. Next to the p-base region, an n+-source region is formed. On the cathode film, an interlayer insulator film is selectively formed on which an emitter electrode is formed. A semiconductor device such as an IGBT is obtained with a high rate of acceptable products, an excellent on-voltage to turn-off loss tradeoff and an excellent on-voltage to breakdown voltage tradeoff.

Abstract: A method of manufacturing a semiconductor device, includes: forming a first and a second trench regions adjacent from each other in a first conductivity type semiconductor base; forming a second conductivity type semiconductor region in the semiconductor base between the first and second trench regions; forming a mask on the second conductivity type semiconductor region, the mask covering a central portion between the first and second trench regions; performing ion implantation of a first conductivity type impurity in the second conductivity type semiconductor region with the mask to form a first conductivity type first region and a first conductivity type second region separated from the first conductivity type first region; and performing heat treatment to diffuse the impurity in the first and second regions and to form a connection region between the first and second regions, connection region being shallower than the first and second regions after the heat treatment.

Abstract: A trench IGBT is disclosed which includes a semiconductor substrate having formed therein a set of cell trenches formed centrally and a set of annular guard trenches concentrically surrounding the cell trenches. The cell trenches receive cell trench conductors via cell trench insulators for providing IGBT cells. The guard trenches receive guard trench conductors via guard trench insulators for enabling the IGBT to withstand higher voltages through mitigation of field concentrations. Capacitive coupling conductors overlie the guard trench conductors via a dielectric layer, each for capacitively coupling together two neighboring ones of the guard trench conductors. The capacitive coupling conductors are easily adjustably variable in shape, size and placement relative to the guard trench conductors for causing the individual guard trench conductors to possess potentials for an optimal contour of the depletion layer.

Abstract: A trench type IGBT as disclosed herein includes a plurality of channel regions having one threshold voltage for the normal operation of the device and a plurality of channel regions having a threshold voltage higher than the threshold voltage for the normal operation of the device.

Abstract: A semiconductor device comprises a semiconductor substrate having a gate trench formed therein. A gate electrode is formed on a gate insulator in the gate trench. The gate electrode has ends close to the bottom of the gate trench, which are separated in a direction perpendicular to both sides of the gate trench, and portions except the separated ends, at least part of which is made higher in conductivity than other parts.

Abstract: A semiconductor device including an n-type semiconductor substrate, a p-type channel region and a junction layer provided between the n-type semiconductor substrate and the p-type channel region is disclosed. The junction layer has n-type drift regions and p-type partition regions alternately arranged in the direction in parallel with the principal surface of the n-type semiconductor substrate. The p-type partition region forming the junction layer is made to have a higher impurity concentration than the n-type drift region. This enables the semiconductor device to have an enhanced breakdown voltage and, at the same time, have a reduced on-resistance.

Abstract: A process for fabricating a power semiconductor device is disclosed.

Abstract: A FET includes a trench in a semiconductor region. The trench has a lower portion with a shield electrode therein, and an upper portion with a gate electrode therein, where the upper portion is wider than the lower portion. The semiconductor region includes a substrate of a first conductivity type and a first silicon region of a second conductivity type over the substrate. The first silicon region has a first portion extending to a depth intermediate top and bottom surfaces of the gate electrode. The first silicon region has a second portion extending to a depth intermediate top and bottom surfaces of the shield electrode. The semiconductor region further includes a second silicon region of the first conductivity type between the lower trench portion and the second portion of the first silicon region that has a laterally-graded doping concentration decreasing in a direction away from the sidewalls of the lower trench portion.

Abstract: A semiconductor device and a method of manufacturing the same capable of preventing a not open fail of a landing plug contact caused by the leaning of a gate. The method includes the steps of preparing a semiconductor substrate, forming first recesses by etching an active area of the semiconductor substrate, filling a conductive layer in the first recesses, forming a second recess by etching a predetermined part of the active area, forming under stepped gates, forming a gate insulating layer on a surface of the semiconductor substrate, forming a channel layer on the gate insulating layer, forming source/drain areas in the semiconductor substrate, forming an interlayer insulating film on an entire surface of the semiconductor substrate, and forming a landing plug in the interlayer insulating film such that the landing plug makes contact with the source/drain areas, respectively.

Abstract: A semiconductor device having recess gates and a method for fabricating the same. The semiconductor device includes a semiconductor substrate having inverse triangular recesses formed therein; a gate insulating film having a designated thickness formed on the semiconductor substrate; gate electrodes formed on the gate insulating film so that the gate electrodes fill the inverse triangular recesses and protrude from the surface of the semiconductor substrate; and first and second junction regions formed in the semiconductor substrate and opposed to each other so that the corresponding one of the gate electrodes is interposed therebetween.

Abstract: A semiconductor body includes a drift zone of a first conduction type. A body zone of a second conduction type complementary to the first conduction type is located near the surface in the semiconductor body. The semiconductor body includes a near-surface field stop zone of the second complementary conduction type and doped more lightly than the body zone.

Abstract: A trench gate type IGBT includes: a first semiconductor layer; a second semiconductor on the first semiconductor layer; a third semiconductor on the second semiconductor layer; trenches for separating the third semiconductor layer into first regions and second regions; a gate insulation film on an inner wall of each trench; a gate electrode on the gate insulation film; a fourth semiconductor layer in a surface portion of each first region and contacting each trench; a first electrode connecting to the first region and the fourth semiconductor layer; and a second electrode connecting to the first semiconductor layer. The first regions and the second regions are alternately arranged. Two second regions are continuously connected together to be integrated into one body.

Abstract: A manufacturing method of metal oxide semiconductor transistor is provided. A substrate is provided. A source/drain extension region is formed in the substrate. A pad material layer with low dielectric constant is formed on the substrate. A trench is formed in the substrate and the pad material layer. A gate dielectric layer is formed on the surface of the substrate in the trench. A stacked gate structure is formed in the trench, wherein the top surface of a conductive layer of the stacked gate structure is higher than the surface of the pad material layer. A spacer material layer is formed conformably on the substrate. Portions of the spacer material layer and the pad material layer are removed so as to form a pair of first spacers and a pair of pad blocks. A source/drain is formed on the substrate beside the stacked gate structure.

Abstract: A semiconductor device (1, 20-80) has an emitter terminal (2), a collector terminal (3) and also a semiconductor body (4) provided between emitter terminal (2) and collector terminal (3). An emitter zone (5, 70) is formed in the semiconductor body (4), said emitter zone at least partially adjoining the emitter terminal (2) and also having a first interface (16) facing the emitter terminal (2) and a second interface (17) facing the collector terminal. The semiconductor device has at least one MOS structure (8, 81) which pervades the emitter zone or adjoins the latter, and which is configured such that corresponding MOS channels (11, 14) induced by the MOS structure (8, 81) within the emitter zone (5, 70) are at a distance from the first interface (16) of the emitter zone (5, 70).

Abstract: This semiconductor device comprises a first semiconductor layer of a first conductivity type, an epitaxial layer of a first conductivity type formed in the surface on the first semiconductor layer, and a base layer of a second conductivity type formed on the surface of the epitaxial layer. Column layers of a second conductivity type are repeatedly formed in the epitaxial layer under the base layer at a certain interval. Trenches are formed so as to penetrate the base layer to reach the epitaxial layer; and gate electrodes are formed in the trenches via a gate insulation film. A termination layer of a second conductivity type is formed on the epitaxial layer at an end region at the perimeter of the base layer. The termination layer is formed to have a junction depth larger than that of the base layer.

Abstract: An emitter layer is provided in stripes in a direction orthogonal to an effective gate trench region connected to a gate electrode and a dummy trench region isolated from the gate electrode. A width of the emitter layer is determined to satisfy a predetermined relational expression so as not to cause latch-up in an underlying P base layer. In the predetermined relational expression, an upper limit value of the width W of the emitter layer is (3500/Rspb)·Wso·exp(decimation ratio), where Rspb is a sheet resistance of the P base layer immediately below the emitter layer, Wso is an interval between the trenches, and the decimation ratio is a ratio of the number of the effective gate trench region to the total number of the trench regions. Variations in saturation current in a trench IGBT can be suppressed, and a tolerance of an Reverse Bias Safe Operation Area can be improved.

Abstract: A vertical semiconductor device includes a vertical, active region including a first semiconductor layer of a first conductivity type, a second semiconductor layer of a second conductivity type, and a third semiconductor layer of the first conductivity type, a trench extending through the third semiconductor layer at least into the second semiconductor layer, the trench comprising a first portion bordering on the third semiconductor layer, and the trench comprising a second portion extending at least into the second semiconductor layer starting from the first portion, an insulating layer associated with a control terminal and at least partially arranged on a side wall of the first portion of the trench and at least partially extending into the second portion of the trench, and a resistive layer with a field-strength-dependent resistance and arranged in the second portion of the trench at least partially on the sidewall and the bottom of the trench.