Abstract: A semiconductor device with a charge carrier compensation structure in a semiconductor body and to a method for its production. The semiconductor body includes drift zones of a first conduction type and charge compensation zones of a second conduction type complementing the first conduction type. The drift zones include a semiconductor material applied in epitaxial growth zones, wherein the epitaxial growth zones include an epitaxially grown semiconductor material which is non-doped to lightly doped. Towards the substrate, the epitaxial growth zones are provided with a first conduction type incorporated by ion implantation over the entire surface and with selectively introduced doping material zones of a second, complementary conduction type. Towards the front side, the epitaxial growth zones are provided with a second, complementary conduction type incorporated by ion implantation over the entire surface and with selectively introduced doping material zones of the first conduction type.

Abstract: According to one embodiment, a semiconductor device includes a first semiconductor layer of a first conductivity type, a second semiconductor layer of the first conductivity type, a third semiconductor layer of a second conductivity type, a fourth semiconductor layer of the second conductivity type, a fifth semiconductor layer of the first conductivity type, a control electrode, a first main electrode, a second main electrode, and a sixth semiconductor layer of the first conductivity type. The second semiconductor layer and the third semiconductor layer are alternately provided on the first semiconductor layer in a direction substantially parallel to a major surface of the first semiconductor layer. The fourth semiconductor layer is provided on the second semiconductor layer and the third semiconductor layer. The fifth semiconductor layer is selectively provided on a surface of the fourth semiconductor layer. The control electrode is provided in a trench via an insulating film.

Abstract: An LDMOS device and a method for fabricating the same that may include a first conductivity-type semiconductor substrate having an active area and a field area; a second conductivity-type deep well formed on the first conductivity-type semiconductor substrate; a second conductivity-type adjusting layer located in the second conductivity-type deep well; a first conductivity-type body formed in the second conductivity-type deep well; an insulating layer formed on the first conductivity-type semiconductor substrate in the active area and the field area; a gate area formed on the first conductivity-type semiconductor substrate in the active area; a second conductivity-type source area formed in the first conductivity-type body; a second conductivity-type drain area formed in the second conductivity-type deep well. Accordingly, such an LDMOS device has a high breakdown voltage without an increase in on-resistance.

Abstract: A semiconductor device includes a high voltage first conduction type well in a semiconductor substrate, a second conduction type body in the high voltage first conduction type well, a source region in the second conduction type body, a trench in the high voltage first conduction type well, a first isolation oxide, an impurity doped polysilicon film, and a second isolation oxide stacked in the trench in succession, a drain region in the high voltage first conduction type well on one side of the trench, and a polygate on and/or over the high voltage first conduction type well.

Abstract: A superjunction semiconductor device includes an edge p pillar, an active region, and a termination region. The edge p pillar has a rectangular ring shape with rounded corners surrounding the active region. The active region includes an active n region and active p pillars having vertical stripe shapes disposed at regular intervals in the active n region. The top and bottom ends of the active p pillars are separated from the edge p pillar. The termination region includes termination n pillars and termination p pillars alternately arranged around the edge p pillar. Surplus p charges that are not used to balance the quantity of p charges and the quantity of n charges among p charges included in the upper and lower parts of the edge p pillar are eliminated or n charges are supplemented to balance the quantity of p charges and the quantity of n charges.

Abstract: The semiconductor apparatus according to the present invention includes: a second-conductivity-type first diffusion region formed on the semiconductor layer; a first-conductivity-type second diffusion region formed in the first diffusion region; a second-conductivity-type first high concentration diffusion region and a first-conductivity-type second high concentration diffusion region formed in the second diffusion region; a second-conductivity-type third high concentration diffusion region, separated by a given distance from the second diffusion region, in the first diffusion region; and a gate electrode formed above and between the first high concentration diffusion region and third high concentration diffusion region, with a gate insulation film interposed therebetween, where the gate electrode is formed overlapping the first high concentration diffusion region, and the gate electrode is electrically connected with the first high concentration diffusion region and second high concentration diffusion region

Abstract: According to the present invention, semiconductor device breakdown voltage can be increased by embedding field shaping regions within a drift region of the semiconductor device. A controllable current path extends between two device terminals on the top surface of a planar substrate, and the controllable current path includes the drift region. Each field shaping region includes two or more electrically conductive regions that are electrically insulated from each other, and which are capacitively coupled to each other to form a voltage divider dividing a potential between the first and second terminals. One or more of the electrically conductive regions are isolated from any external electrical contact. Such field shaping regions can provide enhanced electric field uniformity in current-carrying parts of the drift region, thereby increasing device breakdown voltage.

Abstract: According to one embodiment, a semiconductor device, includes a semiconductor layer, a first base region of a first conductivity type, a first source region of a second conductivity type, a second base region of the first conductivity type, a back gate region of the first conductivity type, a drift region of the second conductivity type, a drain region of the second conductivity type, a first insulating region, a second insulating region, a gate oxide film, a first gate electrode, a second gate electrode, a first main electrode and a second main electrode. These constituent elements are provided on the surface of the semiconductor layer. The distance between the first base region and the first insulating region is not more than 1.8 ?m. The distance between the first base region and the first insulating region is shorter than a distance between the second base region and the second insulating region.

Abstract: The semiconductor device includes: a first conductive-type first well and a second conductive-type second well configured over a substrate to contact each other; a second conductive-type anti-diffusion region configured in an interface where the first conductive-type first well contacts the second conductive-type second well over the substrate; and a gate electrode configured to simultaneously cross the first conductive-type first well, the second conductive-type anti-diffusion region, and the second conductive-type second well over the substrate.

Abstract: The present teaching provides a semiconductor device capable of relaxing stress transferred to a contact region during wire bonding and improving reliability of wire bonding. A semiconductor device comprises contact regions, an interlayer insulating film, an emitter electrode, and a stress relaxation portion. The contact regions are provided at a certain interval in areas exposing at a surface of a semiconductor substrate. The interlayer insulating film is provided on the surface of the semiconductor substrate between adjacent contact regions. The emitter electrode is provided on an upper side of the semiconductor substrate and electrically connected to each of the contact regions. The stress relaxation portion is provided on an upper surface of the emitter electrode in an area only above the contact regions. The stress relaxation portion is formed of a conductive material.

Abstract: A semiconductor device includes a lateral double diffused metal oxide semiconductor (LDMOS) , a junction field effect transistor (JFET) and an inner circuit. The lateral double diffused metal oxide semiconductor includes a first source, a common drain and a first gate. The junction field effect transistor includes a second source, the common drain and a second gate. The second source is electrically connected to the first gate. The inner circuit is electrically connected to the first source.

Abstract: Integrated circuit devices and electrostatic discharge (ESD) protection circuits thereof. An integrated circuit device may include an input/output pad, an internal circuit, and a transistor connected between the input/output pad and the internal circuit configured to perform a switch operation between the input/output pad and the internal circuit in response to a control signal transmitted from the internal circuit, and operate as an ESD protection circuit.

Abstract: A metal-oxide-semiconductor (MOS) device is disclosed. The MOS device includes a substrate of a first impurity type, a diffused region of a second impurity type in the substrate, a patterned first dielectric layer including a first dielectric portion over the diffused region, a patterned first conductive layer on the patterned first dielectric layer, the patterned first conductive layer including a first conductive portion on the first dielectric portion, a patterned second dielectric layer including a second dielectric portion that extends on a first portion of an upper surface of the first conductive portion and along a sidewall of the first conductive portion to the substrate; and a patterned second conductive layer on the patterned second dielectric layer, the patterned second conductive layer including a second conductive portion on the second dielectric portion.

Abstract: According to one embodiment, a semiconductor device including a cell region and a terminal region includes a first semiconductor region of a first conductivity type, semiconductor pillars of the first and a second conductivity type, a second semiconductor region of the second conductivity type, and a third semiconductor region of the first conductivity type. The semiconductor pillars of the first and second conductivity type are and arranged alternately on the first semiconductor region. The second semiconductor region is provided on the semiconductor pillar of the second conductivity type. The third semiconductor region is provided on the second semiconductor region. A semiconductor pillar other than a semiconductor pillar most proximal to the terminal region is provided in a stripe configuration. The semiconductor pillar most proximal to the terminal region includes regions having a high and a low impurity concentration. The regions are provided alternately.

Abstract: A super-junction trench MOSFET with Resurf Stepped Oxide is disclosed. The inventive structure can apply additional freedom for better optimization and manufacturing capability by tuning thick oxide thickness to minimize influence of charge imbalance, trapped charges, etc. . . . . Furthermore, the fabrication method can be implemented more reliably with lower cost.

Abstract: A semiconductor device is provided, which comprises a first transistor and a second transistor formed in a semiconductor layer. The first transistor includes a first source region and a first drain region sandwiching a first gate electrode with the first source region. The second transistor includes an LDD region and a drift region sandwiching the second gate electrode with the LDD region, and a second drain region adjacent to the drift region to sandwich the second gate electrode with the second source region. The first gate electrode has a first sidewall formed on sides thereof and the second gate electrode has a second sidewall formed on sides thereof. The width of the former along the first insulator differs from the width of the latter along the second insulator.

Abstract: A semiconductor component may include a semiconductor layer which has a front side and a back side, a first terminal electrode on the front side, a second terminal electrode on the back side, a first dopant region of a first conduction type on the front side, which is electrically connected to one of the terminal electrodes, a second dopant region of a second conduction type in the semiconductor layer, which is electrically connected to the other terminal electrode, a pn junction being formed between the first and second dopant regions, a dielectric layer on the back side between the semiconductor layer and the second terminal electrode, and the dielectric layer having an opening through which an electrical connection between the second terminal electrode and the first or second dopant region is passed.

Abstract: To fabricate a power MOSFET, etc. high in voltage-proofing (or breakdown voltage) and low in ON resistance (or On-state resistance) by a trench filling method, trial manufacture of power MOSFETs, etc. has been repeated with varying internal structures and layouts of super junction structures in a chip inner region located inside a guard ring. As a result, there occasionally occurred a source-drain voltage-proofing defect attributable to outer end portions of a supper junction structure. In one aspect of the present invention there is provided a semiconductor device having a power semiconductor element with a super junction structure introduced substantially throughout the whole surface of a drift region, the super junction structure being provided substantially throughout the whole surfaces of end portions of a semiconductor chip which configures the semiconductor device.

Abstract: The semiconductor device comprises a first impurity region having a second conductivity type and formed in a semiconductor layer having a first conductivity type; a body region adjacent to and in contact with the first impurity region and having the first conductivity type; a second impurity region formed in the first impurity region, having the second conductivity type, and having a depth smaller than the first impurity region; a source region formed in the body region and having the second conductivity type; a drain region formed in the second impurity region and having the second conductivity type; and a gate electrode formed via a gate insulating film. In a preferable mode of the semiconductor device, the second impurity region has a higher impurity concentration than the first impurity region and the first impurity region has a depth of 1 ?m or smaller.

Abstract: An IGFET device includes: —a semiconductor body having a major surface, —a source region of first conductivity type abutting the surface, —a drain region of the first conductivity-type abutting the surface and spaced from the source region with a channel therefrom, —an active gate overlying the channel and insulated from the channel by a first dielectric material forming the gate oxide of the IGFET device, —a dummy gate positioned between the active gate and the drain and insulated from the active gate by a second dielectric material so that a capacitance is formed between the active gate and the dummy gate, and insulated from the drain region by the gate oxide, wherein the active gate and the dummy gate are forming the electrodes of the capacitance substantially perpendicular to the surface.

Abstract: Disclosed is a high-voltage diode structure which realizes high reverse recovery capability and high maximum allowable forward current. The distance between a longitudinal end of a p well layer in an anode region and an element isolation region formed to surround the diode is 5 ?m or shorter so as to allow a depletion layer to reach the element isolation region when a maximum rated reverse voltage is applied. During reverse recovery, the electric field strength at an end portion of a p well layer is reduced, hole current is reduced, and local temperature rises are reduced.

Abstract: A transistor is formed inside an isolation structure which includes a floor isolation region and a trench extending from the surface of the substrate to the floor isolation region. The trench may be filled with a dielectric material or may have a conductive material in a central portion with a dielectric layer lining the walls of the trench.

Abstract: A method of manufacturing a semiconductor device includes forming a mask layer on a first-conductivity-type semiconductor substrate, etching the semiconductor substrate using the mask layer as a mask, thereby forming a projecting semiconductor layer, forming a first insulating layer on the semiconductor substrate to cover a lower portion of the projecting semiconductor layer, doping a first-conductivity-type impurity into the first insulating layer, thereby forming a high-impurity-concentration layer in the lower portion of the projecting semiconductor layer, forming gate insulating films on side surfaces of the projecting semiconductor layer which upwardly extend from an upper surface of the first insulating layer, and forming a gate electrode on the gate insulating films and on the first insulating film.

Abstract: A semiconductor integrated circuit device and method of fabricating a semiconductor integrated circuit device, the method including preparing a first conductivity type substrate including a first conductivity type impurity such that the first conductivity type substrate has a first impurity concentration; forming a buried impurity layer using blank implant such that the buried impurity layer includes a first conductivity type impurity and has a second impurity concentration higher than the first impurity concentration; forming an epitaxial layer on the substrate having the buried impurity layer thereon; and forming semiconductor devices and a device isolation region in or on the epitaxial layer.

Abstract: Investigation of problems of the device structure of a power MOSFET and mass production of it in relation to high breakdown voltage and low ON resistance when an epitaxy trench filling system is employed has revealed that it has the following problem, that is, a high breakdown voltage as expected cannot be achieved because a P-column region does not have an ideal rectangular parallelepipedal shape but has an inverted trapezoidal shape narrower at the bottom thereof and at the same time, has a concentration distribution lower at the bottom. In order to overcome the problem, the present invention provides a semiconductor device including a power MOSFET portion equipped, in an active cell region thereof, a super junction structure formed by a trench filling system, wherein a base epitaxial layer has a multistage structure with the upper portion having a higher impurity concentration.

Abstract: A semiconductor device according to an embodiment of the present invention includes a device part and a terminal part.

Abstract: A semiconductor structure is provided. A second conductivity type well region is formed on a first conductivity type substrate. A second conductivity type diffused source and second conductivity type diffused drain are formed on the first conductivity type substrate. A gate structure is formed on the second conductivity type well region between the second conductivity type diffused source and the second conductivity type diffused drain. First conductivity type buried rings are arranged in a horizontal direction, and formed in the second conductivity type well region, and divide the second conductivity type well region into an upper drift region and a lower drift region.

Abstract: According to one embodiment, a semiconductor device includes a base region of a second conductivity type, a drift region of a first conductivity type, an insulating layer, a drain region of the first conductivity type, a gate oxide film, a gate electrode, a first main electrode, and a second main electrode. The base region includes a source region of the first conductivity type. The drift region is adjacent to the base region. The insulating layer is provided from a surface to inside of the drift region. The drain region is provided in the surface of the drift region and opposed to the source region across the base region and the insulating layer. The gate oxide film is provided on a surface of the base region. The gate electrode is provided on the gate oxide film. The first main electrode is connected to the source region. The second main electrode is connected to the drain region.

Abstract: A method for forming a doped region of a semiconductor device includes masking a portion of a substrate with a mask. The mask is configured to create a graded doping profile within the doped region. The method also includes performing an implant using the mask to create doped areas and undoped areas in the substrate. The method further includes diffusing the doped areas to create the graded doping profile in the doped region. The mask could include a first region having openings distributed throughout a photo-resist material, where the openings vary in size and spacing. The mask could also include a second region having blocks of photo-resist material distributed throughout an open region, where the photo-resist blocks vary in size and spacing. Diffusing the doped areas could include applying a high temperature anneal to smooth the doped and undoped areas to produce a linearly graded doping profile.

Abstract: A semiconductor device comprising: a first semiconductor layer of a first conductivity type; a second semiconductor layer of the first conductivity type formed on the first semiconductor layer; a first buried layer of the first conductivity type selectively formed in the second semiconductor layer and having a first peak impurity concentration at a first depth; a second buried layer of a second conductivity type selectively formed in the second semiconductor layer and having a second peak impurity concentration at a second depth; a base layer of the second conductivity type selectively formed in the second semiconductor layer and overlapping with an upper portion of the second buried layer; a source layer of the first conductivity type selectively formed in the base layer; and a gate electrode formed on the base layer and on the second semiconductor layer above the first buried layer with a gate insulating film being interposed therebetween.

Abstract: A trenched semiconductor power device includes a trenched gate insulated by a gate insulation layer and surrounded by a source region encompassed in a body region above a drain region disposed on a bottom surface of a semiconductor substrate. The source region surrounding the trenched gate includes a metal of low barrier height to function as a Schottky source. The metal of low barrier height further may include a PtSi or ErSi layer. In a preferred embodiment, the metal of low barrier height further includes an ErSi layer. The metal of low barrier height further may be a metal silicide layer having the low barrier height. A top oxide layer is disposed under a silicon nitride spacer on top of the trenched gate for insulating the trenched gate from the source region. A source contact disposed in a trench opened into the body region for contacting a body-contact dopant region and covering with a conductive metal layer such as a Ti/TiN layer.

Abstract: A semiconductor device is provided that, in an embodiment, is in the form of a high voltage MOS (HVMOS) device. The device includes a semiconductor substrate and a gate structure formed on the semiconductor substrate. The gate structure includes a gate dielectric which has a first portion with a first thickness and a second portion with a second thickness. The second thickness is greater than the first thickness. A gate electrode is disposed on the first and second portion. In an embodiment, a drift region underlies the second portion of the gate dielectric. A method of fabricating the same is also provided.

Abstract: In a high frequency amplifying MOSFET having a drain offset region, the size is reduced and the on-resistance is decreased by providing conductor plugs 13 (P1) for leading out electrodes on a source region 10, a drain region 9 and leach-through layers 3 (4), to which a first layer wirings 11a, 11d (M1) are connected and, further, backing second layer wirings 12a to 12d are connected on the conductor plugs 13 (P1) to the first layer wirings 11s, 11d (M1).

Abstract: The present invention discloses a high voltage metal oxide semiconductor (HVMOS) device and a method for making same. The high voltage metal oxide semiconductor device comprises: a substrate; a gate structure on the substrate; a well in the substrate, the well defining a device region from top view; a first drift region in the well; a source in the well; a drain in the first drift region, the drain being separated from the gate structure by a part of the first drift region; and a P-type dopant region not covering all the device region, wherein the P-type dopant region is formed by implanting a P-type dopant for enhancing the breakdown voltage of the HVMOS device (for N-type HVMOS device) or reducing the ON resistance of the HVMOS device (for P-type HVMOS device).

Abstract: The present disclosure provides a semiconductor device having a transistor. The transistor includes a source region, a drain region, and a channel region that are formed in a semiconductor substrate. The channel region is disposed between the source and drain regions. The transistor includes a first gate that is disposed over the channel region. The transistor includes a plurality of second gates that are disposed over the drain region.

Abstract: A semiconductor device is provided. The semiconductor device includes a gate on a substrate, a source region at a first side of the gate, a first conductive type body region under the source region, a second conductive type drain region at a second side of the gate, a device isolation region in the substrate between the source region and the drain region and overlapping part of the gate, and a first buried layer extending in a direction from the source region to the drain region, the first buried layer under the body region, overlapping part of the device isolation region, and not overlapping the drain region.

Abstract: These various embodiments pertain to an FET having a plurality of fingers as correspond to the FET's source and drain. A first conductive lead electrically couples to a given one of this plurality of fingers while a second conductive lead electrically couples as well to this same given finger. A measurement component connects to these first and second conductive leads to measure at least one electrical parameter (such as voltage). By one approach, the first and second conductive leads physically connect to opposing ends of the given finger. These teachings will also accommodate providing a control component that is responsive to the measurement component to facilitate automatically controlling at least one operating state of the FET as a function, at least in part, of the measured electrical parameter.

Abstract: A superjunction device and methods for layout design and fabrication of a superjunction device are disclosed. A layout of active cell column structures can be configured so that a charge due to first conductivity type dopants balances out charge due to second conductivity type dopants in a doped layer in an active cell region. A layout of end portions of the active cell column structures proximate termination column structures can be configured so that a charge due to the first conductivity type dopants in the end portions and a charge due to the first conductivity type dopants in the termination column structures balances out charge due to the second conductivity type dopants in a portion of the doped layer between the termination column structures and the end portions.

Abstract: A MOS transistor includes a body region of a first conductivity type, a conductive gate and a first dielectric layer, a source region of a second conductivity type formed in the body region, a heavily doped source contact diffusion region formed in the source region, a lightly doped drain region of the second conductivity type formed in the body region where the lightly doped drain region is a drift region of the MOS transistor, a heavily doped drain contact diffusion region of the second conductivity type formed in the lightly doped drain region; and an insulating trench formed in the lightly doped drain region adjacent the drain contact diffusion region. The insulating trench blocks a surface current path in the drift region thereby forming vertical current paths in the drift region around the bottom surface of the trench.

Abstract: A Metal Oxide Semiconductor (MOS) transistor comprising: a source; a gate; and a drain, the source, gate and drain being located in or on a well structure of a first doping polarity located in or on a substrate; wherein at least one of the source and the drain comprises a first structure comprising: a first region forming a first drift region, the first region being of a second doping polarity opposite the first doping polarity; a second region of the second doping polarity in or on the first region, the second region being a well region and having a doping concentration which is higher than the doping concentration of the first region; and a third region of the second doping polarity in or on the second region. Due to the presence of the second region the transistor may have a lower ON resistance when compared with a similar transistor which does not have the second region. The breakdown voltage may be influenced only to a small extent.

Abstract: A semiconductor device eg. a MOSFET (1) comprising a substrate (40) including a first region (18) and a second region (16) of a first conductivity type and a third region (42) between the first and second regions of a type opposite to the first conductivity type, and being covered by a dielectric layer (20), a plurality of trenches (12) laterally extending between the third and second region, said trenches being filled with an insulating material, and being separated by active stripes (14) comprising a doping profile having a depth not exceeding the depth of the trenches wherein each trench terminates before reaching the dielectric layer (20),namely is separated from the third region by a substrate portion (26) such that the respective boundaries between the substrate portions and the trenches are not covered by the dielectric layer. A method for manufacturing such a semiconductor device is also disclosed.

Abstract: A semiconductor device can include a drift region, at least a portion of the drift region located laterally between a drain region and a source region. The drift region can include a first layer having a first doping concentration and a second layer having a second higher doping concentration than the first layer. The second layer of the drift region be configured to allow drift current between the source region and the drain region when a depletion region is formed in at least a portion of the first layer between the source region and the drain region.

Abstract: A semiconductor device includes an n-conductive type semiconductor substrate having a main side and a rear side, a p-conductive type layer arranged over the main side of the substrate, a main side n-conductive type region arranged in the p-conductive type layer, a rear side n-conductive type layer arranged over the rear side of the substrate, a first trench which reaches the substrate and penetrates the main side n-conductive type region and the p-conductive type layer, a second trench which reaches an inside of the p-conductive type layer, a second electrode layer, which is embedded in the second trench and connected to the p-conductive type layer. Hereby, the semiconductor device, in which the recovery property of a diode cell can be improved without damaging the property of a MOS transistor cell or an IGBT cell and the surge withstand property does not deteriorate, can be obtained.

Abstract: A method of fabricating a laterally diffused metal oxide semiconductor (LDMOS) transistor includes forming a dummy gate over a substrate. A source and a drain are formed over the substrate on opposite sides of the dummy gate. A first silicide is formed on the source. A second silicide is formed on the drain so that an unsilicided region of at least one of the drain or the source is adjacent to the dummy gate. The unsilicided region of the drain provides a resistive region capable of sustaining a voltage load suitable for a high voltage LDMOS application. A replacement gate process is performed on the dummy gate to form a gate.

Abstract: High-mobility vertical trench DMOSFETs and methods for manufacturing are disclosed. A source region, a drain region or a channel region of a high-mobility vertical trench DMOSFET may comprise silicon germanium (SiGe) that increases the mobility of the charge carriers in the channel region. In some embodiments the channel region may be strained to increase channel charge carriers mobility.

Abstract: A semiconductor device according to the present invention includes a semiconductor substrate of a first conductivity type having a top surface and a rear surface, a semiconductor layer of a second conductivity type formed on the top surface of the semiconductor substrate, having a top surface and a rear surface, and having the rear surface in contact with the top surface of the semiconductor substrate, a body region of the first conductivity type formed in a top layer portion of the semiconductor layer, a first impurity region of the second conductivity type formed in a top layer portion of the semiconductor layer and spaced apart from the body region, a second impurity region of the second conductivity type formed in a top layer portion of the body region and spaced apart from a peripheral edge of the body region, a gate electrode formed on the semiconductor layer and opposed to a portion between the peripheral edge of the body region and a peripheral edge of the second impurity region, a field insulating fi

Abstract: According to one embodiment, a power semiconductor device includes a first insulating film and a second insulating film. The first insulating film has a first dielectric constant and is formed on a bottom surface and a side surface of a trench formed by a second semiconductor layer. The trench is in contact with a fourth semiconductor layer and extends from a surface of the fourth semiconductor layer through a third semiconductor layer to the second semiconductor layer. The second insulating film is formed on a side surface of the trench formed by the third semiconductor layer and a side surface of the trench formed by the fourth semiconductor layer, being connected to the first insulating film. The second insulating film has a second dielectric constant higher than the first dielectric constant. The gate electrode is buried in the trench via the first and second insulating films.

Abstract: The LDMOS transistor (1) of the invention comprises a source region (3), a channel region (4), a drain extension region (7) and a gate electrode (10). The LDMOS transistor (1) further comprises a first gate oxide layer (8) and a second gate oxide layer (9), which is thicker than the first gate oxide layer (8). The first gate oxide layer (8) at least extends over a first portion of the channel region (4), which is adjacent to the source region (3). The second gate oxide layer (9) extends over a region where a local maximum (A, B) of the electric field (E) generates hot carriers thereby reducing the impact of the hot carriers and reducing the Idq-degradation. In another embodiment the second gate oxide layer (9) extends over a second portion of the channel region (4), which mutually connects the drain extension region (7) and the first portion of the channel region (4), thereby improving the linear efficiency of the LDMOS transistor (1).

Abstract: In a high withstand voltage transistor of a LOCOS offset drain type having a buried layer, a plurality of stripe-shaped diffusion layers are formed below a diffusion layer ranging from an offset layer to a drain layer and a portion between the drain region and the buried layer is depleted completely; thus, a withstand voltage between the drain region and the buried layer is improved. By the formation of the stripe-shaped diffusion layers, the drain region becomes widened; thus, on-resistance is reduced. Further, the buried layer is made high in concentration so as to sufficiently suppress an operation of a parasitic bipolar transistor.

Abstract: According to one embodiment, a semiconductor device having an overlapping multi-well implant comprises an isolation structure formed in a semiconductor body, a first well implant formed in the semiconductor body surrounding the isolation structure, and a second well implant overlapping at least a portion of the first well implant. The disclosed semiconductor device, which may be an NMOS or PMOS device, can further comprise a gate formed over the semiconductor body adjacent to the isolation structure, wherein the first well implant extends a first lateral distance under the gate and the second well implant extends a second lateral distance under the gate, and wherein the first and second lateral distances may be different. In one embodiment, the disclosed semiconductor device is fabricated as part of an integrated circuit including a power management circuit or a power amplifier.