Abstract: A semiconductor device includes a substrate; a first gate stack disposed on the substrate; a second gate stack disposed on the substrate, wherein a metal component of the first gate stack is different from a metal component of the second gate stack; and a dielectric structure disposed over the substrate and between the first gate stack and the second gate stack, in which the dielectric structure is separated from the first gate stack and the second gate stack, and a distance between the dielectric structure and the first gate stack is substantially equal to a distance between the dielectric structure and the second gate stack.

Abstract: According to one embodiment, an apparatus includes at least one vertical transistor, where the at least one vertical transistor includes: a substrate including a semiconductor material; an array of three dimensional (3D) structures above the substrate; and an isolation region positioned between the 3D structures. Each 3D structure includes the semiconductor material. Each 3D structure also includes a first region having a first conductivity type and a second region having a second conductivity type, where the second region includes a portion of at least one vertical sidewall of the 3D structure.

Abstract: According to one embodiment, an apparatus includes a substrate, and at least one three dimensional (3D) structure above the substrate. The substrate and the 3D structure each include a semiconductor material. The 3D structure also includes: a first region having a first conductivity type, and a second region coupled to a portion of at least one vertical sidewall of the 3D structure.

Abstract: A semiconductor device includes a fin patterned in a substrate; a gate disposed over and substantially perpendicular to the fin; a pair of epitaxial contacts including a III-V material over the fin and on opposing sides of the gate; and a channel region between the pair of epitaxial contacts under the gate including an undoped III-V material between doped III-V materials, the doped III-V materials including a dopant in an amount in a range from about 1e18 to about 1e20 atoms/cm3 and contacting the epitaxial contacts.

Abstract: A low voltage transient voltage suppressing (TVS) device supported on a semiconductor substrate supporting an epitaxial layer to form a bottom-source metal oxide semiconductor field effect transistor (BS-MOSFET) that comprises a trench gate surrounded by a drain region encompassed in a body region disposed near a top surface of the semiconductor substrate. The drain region interfaces with the body region constituting a junction diode. The drain region on top of the epitaxial layer constituting a bipolar transistor with a top electrode disposed on the top surface of the semiconductor functioning as a drain/collector terminal and a bottom electrode disposed on a bottom surface of the semiconductor substrate functioning as a source/emitter electrode. The body regions further comprises a surface body contact region electrically connected to a body-to-source short-connection thus connecting the body region to the bottom electrode functioning as the source/emitter terminal.

Abstract: A supply-voltage-fluctuation detecting apparatus includes a first detecting unit, a second detecting unit, a capacitor, and a fluctuation detecting unit. The first detecting unit and the second detecting unit detect fluctuations in voltage at a detected voltage input with respect to a detected ground input. A load unit that operates with power supplied from a battery and the first detecting unit are connected in parallel. A detected voltage input of the second detecting unit connects to a positive electrode of the battery. A detected ground input of the second detecting unit connects to a detected ground input of the first detecting unit via an impedance component. The capacitor is connected in parallel to the second detecting unit. The fluctuation detecting unit detects fluctuations in supply voltage when at least one of the first detecting unit or the second detecting unit detects fluctuations in voltage.

Abstract: An electronic device can include different vertical conductive structures that can be formed at different times. The vertical conductive structures can have the same or different shapes. In an embodiment, an insulating spacer can be used to help electrically insulate a particular vertical conductive structure from another part of the workpiece, and an insulating spacer may not be used to electrically isolate a different vertical conductive structure. The vertical conductive structures can be tailored for particular electrical considerations or to a process flow when formation of other electronic components may also be formed within either or both of the particular vertical conductive structures.

Abstract: A semiconductor configuration, which includes an epitaxial layer of the first conductivity type disposed on a highly doped substrate of first conductivity type; a layer of a second conductivity type introduced into the epitaxial layer; and a highly doped layer of the second conductivity type provided at the surface of the layer of the second conductivity type. Between the layer of the second conductivity type and the highly doped substrate of the first conductivity type, a plurality of Schottky contacts, which are in the floating state, are provided mutually in parallel in the area of the epitaxial layer.

Abstract: According to one embodiment, a nitride semiconductor device including a device region and a guard ring formation region surrounding the device region, the nitride semiconductor device includes a first nitride semiconductor layer provided in the device region and the guard ring formation region; a second nitride semiconductor layer provided on the first nitride semiconductor layer and forming a hetero-junction with the first nitride semiconductor layer; and a shielding layer provided on the second nitride semiconductor layer in the guard ring formation region and electrically protecting the device region. A two-dimensional electron gas is present near an interface between the first nitride semiconductor layer and the second nitride semiconductor layer within the first nitride semiconductor layer below the shielding layer, and the shielding layer is in ohmic contact with the two-dimensional electron gas.

Abstract: A bipolar semiconductor component includes a semiconductor body having first and second substantially parallel main surfaces and at least one load pn junction, a first metallization on the first surface, a second metallization on the second surface, and a current path running in the semiconductor body from the first metallization to the second metallization only through n-doped zones, including between first and second p-doped zones which are in contact with the first metallization and spaced apart from one another by an n-doped channel zone through which the current path runs. A space charge region forms in the semiconductor body between the first and second p-doped zones to fully deplete the n-doped channel zone between the first and second p-doped zones and therefore prevent current flow between the first and second metallizations along the current path when a positive voltage is applied between the second metallization and the first metallization.

Abstract: A high voltage junction field effect transistor and a manufacturing method thereof are provided. The high voltage junction field effect transistor includes a base, a drain, a source and a P type top layer. The drain and the source are disposed above the base. A channel is formed between the source and the drain. The P type top layer is disposed above the channel.

Abstract: A semiconductor device includes a substrate, a body region adjoining the substrate surface, a source contact region within the body region, a drain contact region adjoining the substrate surface and being separated from the body region, a dual JFET gate region located between the body region and the drain contact region, and a lateral JFET channel region adjoining the surface of the substrate and located between the body and the drain contact regions. A vertical JFET gate region is arranged essentially enclosed by the body region, a vertical JFET channel region being arranged between the enclosed vertical JFET gate and the dual JFET gate regions, a reduced drain resistance region being arranged between the dual JFET gate and the drain contact regions, and a buried pocket located under part of the body region, under the dual JFET gate region and under the vertical JFET channel and reduced drain resistance regions.

Abstract: An object of the present invention is to propose a functional element built-in substrate which enables an electrode terminal of a functional element to be well connected to the back surface on the side opposite to the electrode terminal of the functional element, and which can be miniaturized.

Abstract: A silicon epitaxial wafer having a silicon epitaxial layer grown by vapor phase epitaxy on a main surface of a silicon single crystal substrate, wherein the main surface of the silicon single crystal substrate is tilted with respect to a [100] axis at an angle ? in a [011] direction or a [0-1-1] direction from a (100) plane and at an angle ? in a [01-1] direction or a [0-11] direction from the (100) plane, the angle ? and the angle ? are less than ten minutes, and a dopant concentration of the silicon epitaxial layer is equal to or more than 1×1019/cm3. Even when an epitaxial layer having a dopant concentration of 1×1019/cm3 or more is formed on the main surface of the silicon single crystal substrate, stripe-shaped surface irregularities on the epitaxial layer are inhibited.

Abstract: A power semiconductor device of the present invention has an active region and an electric field reduction region and includes: an emitter region of a first conductivity type; a base region of a second conductivity type in contact with the emitter region; an electrical strength providing region of the first conductivity type in contact with the base region; a collector region of the second conductivity type in contact with the electrical strength providing region; and a collector electrode in contact with the collector region; wherein the collector region is disposed on both a active region and a electric field reduction region each containing a dopant of the second conductivity type, and the collector region disposed on the electric field reduction region includes a region having a lower density of carriers of the second conductivity type than the collector region disposed on the active region.

Abstract: Embodiments of an integrated circuit are provided. In one embodiment, the integrated circuit includes a substrate and a plurality of locally interconnected multi-gate transistors. The plurality of locally interconnected multi-gate transistors includes a continuous fin structure formed on the substrate and first and second multi-gate transistors formed on the substrate and including first and second fin segments of the continuous fin structure, respectively. The continuous fin structure electrically interconnects the first and second multi-gate transistors.

Abstract: A method of fabricating a non-volatile memory is provided. A tunneling dielectric layer and a first patterned conductive layer are sequentially formed on a substrate. A patterned inter-gate dielectric layer and a second patterned conductive layer are stacked on a first surface of the first patterned conductive layer, and a second surface of the first patterned conductive layer is exposed. The second surface is adjacent to the first surface. The substrate is covered by a passivation layer, and a first sidewall of the first patterned conductive layer is exposed. A recess is formed on the first sidewall of the first patterned conductive layer, such that the first sidewall has a sharp corner. A portion of the passivation layer on the second surface is removed, such that the sharp corner of the first patterned conductive layer is exposed.

Abstract: The disclosure relates generally to junction gate field effect transistor (JFET) structures and methods of forming the same. The JFET structure includes a p-type substrate having a p-region therein; an n-channel thereunder; and n-doped enhancement regions within the n-channel, each n-doped enhancement region separated from the p-region.

Abstract: The objective of this invention is to provide a photodiode which has high sensitivity even to light with a wavelength in the blue region while maintaining the high-frequency characterstics. The n type second semiconductor layer (13) containing an n type electroconductive impurity at a low concentration is formed directly or via an intrinsic semiconductor layer (11) on the p type first semiconductor layer (10). The third semiconductor layer (20) containing an n type electroconductive impurity at a medium concentration is formed shallower than said second semiconductor layer (13) in its main plane. The fourth semiconductor layer (21) containing an n type electroconductive impurity at a high concentration is formed shallower than said third semiconductor layer (20) in the main plane of the third semiconductor layer (20).

Abstract: A drift layer has a thickness direction throughout which a current flows and has an impurity concentration N1d for a first conductivity type. A body region is provided on a portion of the drift layer, has a channel to be switched by a gate electrode, has an impurity concentration N1b for the first conductivity type, and has an impurity concentration N2b for the second conductivity type greater than the impurity concentration N1b. A JFET region is disposed adjacent to the body region on the drift layer, has an impurity concentration N1j for the first conductivity type, and has an impurity concentration N2j for the second conductivity type smaller than the impurity concentration N1j. N1j?N2j>N1d and N2j<N2b are satisfied.

Abstract: In one implementation, a stacked composite device comprises a group IV vertical transistor and a group III-V transistor stacked over the group IV vertical transistor. A drain of the group IV vertical transistor is in contact with a source of the group III-V transistor, a source of the group IV vertical transistor is coupled to a gate of the group III-V transistor to provide a composite source on a bottom side of the stacked composite device, and a drain of the group III-V transistor provides a composite drain on a top side of the stacked composite device. A gate of the group IV vertical transistor provides a composite gate on the top side of the stacked composite device.

Abstract: A semiconductor device as described herein includes a body region of a first conductivity type adjoining a channel region of a second conductivity at a first side of the channel region. A gate control region of the first conductivity type adjoins the channel region at a second side of the channel region opposed to the first side, the channel region being configured to be controlled in its conductivity by voltage application between the gate control region and the body region. A source zone of the second conductivity type is arranged within the body region and a channel stop zone of the second conductivity type is arranged at the first side, the channel stop zone being arranged at least partly within at least one of the body region and the channel region. The channel stop zone includes a maximum concentration of dopants lower than a maximum concentration of dopants of the source zone.

Abstract: Wide bandgap semiconductor devices including normally-off VJFET integrated power switches are described. The power switches can be implemented monolithically or hybridly, and may be integrated with a control circuit built in a single- or multi-chip wide bandgap power semiconductor module. The devices can be used in high-power, temperature-tolerant and radiation-resistant electronics components. Methods of making the devices are also described.

Abstract: This semiconductor device comprises a semiconductor substrate, a gate insulating film formed thereon, and a gate electrode formed through the gate insulating film on the semiconductor substrate. The first silicon nitride film is formed on the upper surface of the gate electrode, and a protection insulating film is formed on the side thereof. The second silicon nitride film is formed on the side of the protection insulating film. The third silicon nitride film is formed on the upper surface of the protection insulating film, and the bottom thereof is formed on a higher position than the bottom of the first silicon nitride film.

Abstract: Disclosed are embodiments of an improved multi-gated field effect transistor (MUGFET) structure and method of forming the MUGFET structure so that it exhibits a more tailored drive current. Specifically, the MUGFET incorporates multiple semiconductor fins in order to increase effective channel width of the device and, thereby, to increase the drive current of the device. Additionally, the MUGFET incorporates a gate structure having different sections with different physical dimensions relative to the semiconductor fins in order to more finely tune device drive current (i.e., to achieve a specific drive current). Optionally, the MUGFET also incorporates semiconductor fins with differing widths in order to minimize leakage current caused by increases in drive current.

Abstract: A semiconductor device includes: a substrate; and depletion and enhancement mode JFETs. The depletion mode JFET includes: a concavity on the substrate; a channel layer in the concavity; a first gate region on the channel layer; first source and drain regions on respective sides of the first gate region in the channel layer; first gate, source and drain electrodes. The enhancement mode JFET includes: a convexity on the substrate; the channel layer on the convexity; a second gate region on the channel layer; second source and drain regions on respective sides of the second gate region in the channel layer; second gate, source and drain electrodes. A thickness of the channel layer in the concavity is larger than a thickness of the channel layer on the convexity.

Abstract: At least one source/drain zone (140, 142, 160, or 162) of an enhancement-mode insulated-gate field-effect transistor (120 or 122) is provided with graded junction characteristics to reduce junction capacitance, thereby increasing switching speed. Each graded junction source/drain zone contains a main portion (140M, 142M, 160M, or 162M) and a more lightly doped lower portion (140L, 142L, 160L, or 162L) underlying, and vertically continuous with, the main portion. The magnitudes of the threshold voltages of a group of such transistors fabricated under the same post-layout fabrication process conditions so as to be of different channel lengths reach a maximum absolute value VTAM when the channel length is at a value LC, are at least 0.03 volt less than VTAM when the channel length is approximately 0.3 ?m greater than LC, and materially decrease with increasing channel length when the channel length is approximately 1.0 ?m greater than LC.

Abstract: Semiconductor devices and methods of making the devices are described. The devices can be junction field-effect transistors (JFETs). The devices have raised regions with sloped sidewalls which taper inward. The sidewalls can form an angle of 5° or more from vertical to the substrate surface. The devices can have dual-sloped sidewalls in which a lower portion of the sidewalls forms an angle of 5° or more from vertical and an upper portion of the sidewalls forms an angle of <5° from vertical. The devices can be made using normal (i.e., 0°) or near normal incident ion implantation. The devices have relatively uniform sidewall doping and can be made without angled implantation.

Abstract: Each of a pair of like-polarity IGFETs (40 or 42 and 240 or 242) has a channel zone (64 or 84) situated in body material (50). Short-channel effects are alleviated by arranging for the net dopant concentration in the channel zone to longitudinally reach a local surface minimum at a location between the IGFET's source/drain zones (60 and 62 or 80 and 82) and by arranging for the net dopant concentration in the body material to reach a local subsurface maximum more than 0.1 ?m deep into the body material but not more than 0.4 ?m deep into the body material. A pocket portion (100/102 or 104) extends along both source drain zones of one of the IGFETs. A pocket portion (244 or 246) extends largely along only one of the source/drain zones of the other IGFET so that it is an asymmetrical device.

Abstract: A complementary metal-oxide silicon (CMOS) image sensor includes a semiconductor layer of a first conductivity type, a plurality of pixels located in the semiconductor layer, a photoelectric converter located in each of the plurality of pixels in the semiconductor layer and includes a region doped with impurities of a second conductivity type. The CMOS image sensor further includes a deep well of a first conductivity type located in a lower position than the photoelectric converter in the semiconductor layer and has a higher impurity concentration than that of the semiconductor layer. The deep well is located only in a portion of each of the plurality of pixels.

Abstract: A dual gate power switch comprised of a vertical arrangement of a normally off SIT (static induction transistor) in series with a normally on SIT in a monolithic semiconductor structure. The structure includes a first pillar having at the base thereof laterally extending shoulder portions having sections of a first gate for controlling the normally off SIT. The structure includes a second pillar, of a width greater than the first pillar and which also has laterally extending shoulder portions having sections of a second gate for controlling the normally on SIT. Contacts are provided for SIT operation.

Abstract: A high-breakdown-voltage semiconductor device comprises a high-resistance semiconductor layer, trenches formed on the surface thereof in a longitudinal plane shape and in parallel, first regions formed on the semiconductor layer to be sandwiched between adjacent ones of the trenches and having an impurity concentration higher than that of the semiconductor layer, a second region having opposite conductivity to the first regions and continuously disposed in a trench sidewall and bottom portion, a sidewall insulating film disposed on the second region of the trench sidewall, a third region disposed on the second region of the trench bottom portion and having the same conductivity as and the higher impurity concentration than the second region, a fourth region disposed on the back surface of the semiconductor layer, a first electrode formed on each first region, a second electrode connected to the third region, and a third electrode formed on the fourth region.

Abstract: A semiconductor device includes a substrate having a pair of first diffused regions, and a gate including an oxide film provided on the substrate, and a charge storage layer provided on the oxide film, the charge storage layer being an electrical insulator capable of storing charges in bit areas. The oxide film has first portions related to the bit areas and a second portion that is located between the bit areas and is thicker than the first potions. The first portions serve as tunneling oxide portions, while the second portion allows reduced tunneling.

Abstract: The invention is directed to a memory cell on a substrate having a plurality of shallow trench isolations form therein, wherein top surfaces of the shallow trench isolations are lower than a top surface of the substrate and the shallow trench isolations together define a vertical fin structure of the substrate. The memory cell comprises a straddle gate, a carrier trapping structure and at least two source/drain regions. The straddle gate is located on the substrate and straddles over the vertical fin structure. The carrier trapping structure is located between the straddle gate and the substrate, wherein the carrier trapping structure comprises a trapping layer directly in contact with the straddle gate and a tunnel layer located between the trapping layer and the substrate. The source/drain regions are located in a portion of the vertical fin structure of the substrate exposed by the straddle gate.

Abstract: A junction field effect transistor (JFET) with a reduced gate capacitance. A gate definition spacer is formed on the wall of an etched trench to establish the lateral extent of an implanted gate region for a JFET. After implant, the gate is annealed. In addition to controlling the final junction geometry and thereby reducing the junction capacitance by establishing the lateral extent of the implanted gate region, the gate definition spacer also limits the available diffusion paths for the implanted dopant species during anneal. Also, the gate definition spacer defines the walls of a second etched trench that is used to remove a portion of the p-n junction, thereby further reducing the junction capacitance.

Abstract: A semiconductor device includes a semiconductor substrate, a first and second semiconductor regions formed on the semiconductor substrate insulated and separated from each other, a gate dielectric film formed on the substrate to overlap the first and second semiconductor regions, a floating gate electrode formed on the gate dielectric film and in which a coupling capacitance of the first semiconductor region is larger than that of the second semiconductor region, first source and drain layers formed on the first semiconductor region to interpose the floating gate electrode therebetween, a first and second wiring lines connected to the first source and drain layers, respectively, second source and drain layers formed on the second semiconductor region to interpose the floating gate electrode therebetween, and a third wiring line connected to the second source and drain layers in common.

Abstract: A dose of arsenic for an extension region in an NMOS transistor is in a range from 5×1014 to 2×1015 ions/cm2 and preferably in a range from 1.1×1015 to 1.5×1015 ions/cm2. Also, in addition to arsenic, a low concentration of phosphorus is doped into the extension region by ion implantation. Consequently, with a semiconductor device of the CMOS structure, it is possible to prevent unwanted creeping of silicide that occurs often in the shallow junction region depending on a concentration of an impurity having a low diffusion coefficient as represented by arsenic. Further, not only can the resistance in the shallow junction region be lowered, but also an amount of overlaps can be optimized in each transistor.

Abstract: A multiple doped channel in a multiple doped gate junction field effect transistor. In accordance with a first embodiment of the present invention, a junction field effect transistor (JFET) circuit structure comprises a vertical channel. The vertical channel comprises multiple doping regions. The vertical channel may comprise a first region for enhancement mode operation and a second region for depletion mode operation.

Abstract: A transistor switch for a system operating at high frequencies is provided. The transistor switch comprises a graded channel region between a source region and a drain region, the graded channel region configured for providing a low resistance to mobile negative charge carriers moving from the source region to the drain region, wherein the graded channel comprises at least two doping levels.

Abstract: According to one aspect of the invention, a method of constructing a memory array is provided. An insulating layer is formed on a semiconductor wafer. A first metal stack is then formed on the insulating layer and etched to form first metal lines. A polymeric layer is formed over the first metal lines and the insulating layer. A puddle of smoothing solvent is then allowed to stand on the wafer. The smoothing solvent is then removed. After the smoothing solvent is removed, the polymeric layer has a reduced surface roughness. A second metal stack is then formed on the polymeric layer and etched to form second metal lines.

Abstract: A silicon carbide semiconductor device includes: a semiconductor substrate including first and second gate layers, a channel layer, a source layer, and a trench; a gate wiring having a first portion and a plurality of second portions; and a source wiring having a third portion and a plurality of fourth portions. The trench extends in a predetermined extending direction. The first portion connects to the first gate layer in the trench, and extends to the extending direction. The second portions protrude perpendicularly to be a comb shape. The third portion extends to the extending direction. The fourth portions protrude perpendicularly to be a comb shape, and electrically connect to the source layer. Each of the second portions connects to the second gate layer through a contact hole.

Abstract: A high-breakdown-voltage semiconductor device comprises a high-resistance semiconductor layer, trenches formed on the surface thereof in a longitudinal plane shape and in parallel, first regions formed on the semiconductor layer to be sandwiched between adjacent ones of the trenches and having an impurity concentration higher than that of the semiconductor layer, a second region having opposite conductivity to the first regions and continuously disposed in a trench sidewall and bottom portion, a sidewall insulating film disposed on the second region of the trench sidewall, a third region disposed on the second region of the trench bottom portion and having the same conductivity as and the higher impurity concentration than the second region, a fourth region disposed on the back surface of the semiconductor layer, a first electrode formed on each first region, a second electrode connected to the third region, and a third electrode formed on the fourth region.

Abstract: The object of the present invention is to provide a semiconductor device, which is suitable for use to connect electric condenser microphones. A semiconductor device, comprises: a conductivity-type substrate; an epitaxial layer formed on top of the substrate; island regions separating the epitaxial layer; an input transistor formed on one of the island regions; an insulation layer covering the surface of the input transistor layer; an expansion electrode formed above the insulation layer so as to provide an electrical connection to an input terminal of the input transistor; and resistivity of the epitaxial layer formed below the expansion electrode being in a range of 1000˜5,000 ?·cm.

Abstract: A manufacturing method for fabricating flash memory semiconductor devices is disclosed.

Abstract: A self aligned method of forming a semiconductor memory array of floating gate memory cells in a semiconductor substrate, and an array formed thereby, whereby each memory cell includes a trench formed into a surface of a semiconductor substrate, spaced apart source and drain regions with a channel region formed therebetween. The drain region is formed underneath the trench, and the channel region includes a first portion that extends substantially vertically along a sidewall of the trench and a second portion that extends substantially horizontally along the surface of the substrate. An electrically conductive floating gate is formed over and insulated from at least a portion of the channel region and a portion of the source region. An electrically conductive control gate is formed having a first portion disposed in the trench and a second portion formed over but insulated from the floating gate.

Abstract: A structure is provided that ensures a low on-resistance and a better blocking effect. In a lateral type SIT (Static Induction Transistor) in which a first region is used as a p+ gate and a gate electrode is formed on the bottom of the first region, the structure is built such that the p+ gate and an n+ source are contiguous. An insulating film is formed on the surface of an n? channel, and an auxiliary gate electrode is formed on the insulating film. In addition, the auxiliary gate electrode and the source electrode are shorted.

Abstract: A junction field effect transistor (JFET) is provided that is capable of a high voltage resistance, high current switching operation, that operates with a low loss, and that has little variation. This JFET is provided with a gate region (2) of a second conductivity type provided on a surface of a semiconductor substrate, a source region (1) of a first conductivity type, a channel region (10) of the first conductivity type that adjoins the source region, a confining region (5) of the second conductivity type that adjoins the gate region and confines the channel region, a drain region (3) of the first conductivity type provided on a reverse face, and a drift region (4) of the first conductivity type that continuously lies in a direction of thickness of the substrate from a channel to a drain.

Abstract: A high-breakdown-voltage semiconductor device comprises a high-resistance semiconductor layer, trenches formed on the surface thereof in a longitudinal plane shape and in parallel, first regions formed on the semiconductor layer to be sandwiched between adjacent ones of the trenches and having an impurity concentration higher than that of the semiconductor layer, a second region having opposite conductivity to the first regions and continuously disposed in a trench sidewall and bottom portion, a sidewall insulating film disposed on the second region of the trench sidewall, a third region disposed on the second region of the trench bottom portion and having the same conductivity as and the higher impurity concentration than the second region, a fourth region disposed on the back surface of the semiconductor layer, a first electrode formed on each first region, a second electrode connected to the third region, and a third electrode formed on the fourth region.

Abstract: In a trench MOS gate structure of a semiconductor device where trenches (T) are located between an n-type base layer (1) and an n-type source layer (3), a p-type channel layer (12) is formed adjacent to side walls of the trenches, having an even concentration distribution along a depthwise dimension of the trenches. The p-type channel layer enables saturation current to decrease without a raise of ON-resistance of the device, and resultantly a durability against short-circuit can be enhanced. The n-type source layer formed adjacent to the side walls of the trench also further enhances the durability against short-circuit. Providing contacts of the emitter electrode (7) with the n-type source layer at the side walls of the trenches permits a miniaturization of the device and a reduction of the ON-resistance as well.

Abstract: In a static induction transistor, in addition to a first gate layer (4), a plurality of second gate layers (41) having a shallower depth and a narrower gap therebetween than those of the first gate layer (4) are provided in an area surrounded by the first gate layer (4), thereby an SiC static induction transistor with an excellent off characteristic is realized, while ensuring a required processing accuracy during production thereof.