Abstract: Semiconductor power device including a semiconductor layer of a first type of conductivity, wherein a body region of a second type of conductivity including source regions of the first type of conductivity is formed, a gate oxide layer superimposed to the semiconductor layer with an opening over the body region, polysilicon regions superimposed to the gate oxide layer, and regions of a first insulating material superimposed to the polysilicon regions. The device includes regions of a second insulating material situated on a side of both the polysilicon regions and the regions of a first insulating material and over zones of the gate oxide layer situated near the opening on the body region, oxide regions interposed between the polysilicon regions and the regions of a second insulating material, oxide spacers superimposed to the regions of a second insulating material.

Abstract: A semiconductor device improves the gate withstand voltage of vertical MOSFETs and raises their operation speed. The gate electrode is formed in the trench of the second semiconductor layer. The interlayer dielectric layer has the contact hole that exposes the connection portion of the gate electrode, where the connection portion is located in the trench. The conductive plug is filled in the contact hole of the interlayer dielectric layer in such a way as to contact the connection portion of the gate electrode. The wiring layer is formed on the interlayer dielectric layer in such a way as to contact the plug, resulting in the wiring layer electrically connected to the connection portion by way of the plug. There is no need to form a connection portion for the gate electrode outside of the trench, which means that the gate dielectric does not include a weak or thinner portion where dielectric breakdown is likely to occur.

Abstract: A double-diffused metal-oxide-semiconductor (“DMOS”) field-effect transistor (10) with a metal gate (26). A sacrificial gate layer is patterned to provide a self-aligned source mask. The source regions (20) are thus aligned to the gate (26), and the source diffusion provides a slight overlap (28) for good turn-on characteristics and low leakage. The sacrificial gate layer is capable of withstanding the diffusion temperatures of the DMOS process and is selectively etchable. After the high-temperature processing is completed, the sacrificial gate layer is stripped and a metal gate layer is formed over the substrate, filling the volume left by the stripped sacrificial gate material. In one embodiment, a chemical-mechanical polishing technique is used to planarize the metal gate layer.

Abstract: In a process of producing a SiC device, a Si layer is formed on the surface of a SiC substrate, and the Si layer is removed from the surface of the SiC substrate by supplying oxygen gas to the Si layer in a high ambient temperature and a low ambient pressure. The pressure is set at 1×10−2 to 1×10−6 Pa. Thus a cleaned surface of the SiC substrate, not contaminated by carbon and the like in atmospheric air, can be provided. Preferably, the oxygen pressure and temperature are set at about 10−6 Pa and 1000° C. for removing the Si layer. Thereafter, the oxygen is further supplied to raise the pressure to about 104 Pa to form an oxide film on the cleaned SiC substrate. Thus, the SiC substrate is cleaned and then formed with the oxide layer in the same chamber by changing the ambient pressure but without changing the ambient temperature.

Abstract: An N+ buffer layer formed on the underside of an N− layer includes an inactive region having incompletely activated ions and an active region having highly activated ions. The carrier concentration of the active region is higher than that of the inactive region. In the inactive region, the electrical activation rate X of the ions is expressed as 1%≦X≦30%. It is thus possible to achieve a PT structure using a Raw wafer, which reduces manufacturing costs and suppresses power consumption.

Abstract: A MOS technology power device comprises a semiconductor material layer of a first conductivity type, a conductive insulated gate layer covering the semiconductor material layer, and a plurality of elementary functional units. The conductive insulated gate layer includes a first insulating material layer placed above the semiconductor material layer, a conductive material layer placed above the first insulating material layer, and a second insulating material layer placed above the conductive material layer. Each elementary functional unit includes an elongated body region of a second conductivity type formed in the semiconductor material layer. Each elementary functional unit further includes an elongated window in the insulated gate layer extending above the elongated body region. Each elongated body region includes a source region doped with dopants of the first conductivity type, intercalated with a portion of the elongated body region wherein no dopant of the first conductivity type are provided.

Abstract: A semiconductor device includes a first region of semiconductor material, which is doped to a first concentration with a dopant of a first conductivity type. A gate trench formed within the first region has sides and a bottom. A drain access trench is also formed within the first region, which also has sides and a bottom. A second region of semiconductor material is located within the first region and adjacent to and near the bottom of the gate trench. The second region extends to a location adjacent to and near the bottom of the drain access trench. The second region is of the first conductivity type and has a higher dopant concentration than the first region. A gate electrode is formed within the gate trench. A layer of gate dielectric material insulates the gate electrode from the first and second regions. A drain region of semiconductor material is located within the drain access trench. The drain region is of a first conductivity type and has a higher dopant concentration than the first region.

Abstract: A vertical double diffuses MOSFET includes a nitride film (26) formed on a gate electrode (18). An ion implant window (34) is formed through the nitride film. P-type ions are implanted through the ion implant window into the semiconductor substrate (12), and the implanted ions are diffused to thereby form a main diffusion region (14). At the same time, the oxide film is grown inside the ion implant window to form a thick walled portion (36). Ions of the p-type are implanted through, as a mask, the thick walled portion, gate electrode and nitride film into semiconductor substrate, and thermally diffused thus forming a channel diffusion region (22). Further, n-type ions are implanted through the same mask and then thermally diffused to provide source diffusion regions.

Abstract: A novel super-self-aligned (SSA) structure and manufacturing process uses a single photomasking layer to define critical features and dimensions of a trench-gated vertical power DMOSFET. The single critical mask determines the trench surface dimension, the silicon source-body mesa width between trenches, and the dimensions and location of the silicon mesa contact. The contact is self-aligned to the trench, eliminating the limitation imposed by contact-to-trench mask alignment in conventional trench DMOS devices needed to avoid process-induced gate-to-source shorts. Oxide step height above the silicon surface is also reduced avoiding metal step coverage problems. Poly gate bus step height is also reduced. Other features described include polysilicon diode formation, controlling the location of drain-body diode breakdown, reducing gate-to-drain overlap capacitance, and utilizing low-thermal budget processing techniques.

Abstract: A method of making a light emitting diode (LED) is disclosed. An emitting light absorbed by a substrate can be prevented by using a metal with high conductivity and high reflectivity and a bonding process can be produced at a lower temperature and a better welding performance can be obtained by using a solder layer could be fused into a liquid-state. Furthermore, an industry standard vertical LED chip structure is provided and only requiring a single wire bond that results in easy LED assembly and the manufacture cost can be reduced. An LED chip size can be greatly reduced and with good heat dissipation, therefore the LED has better reliability performance and can be operated at much higher current.

Abstract: A process for the manufacture of a non-volatile memory with memory cells arranged in word lines and columns in a matrix structure, with source lines extending parallel and intercalate to said lines, said source lines formed by active regions intercalated to field oxide zones, said process comprising steps for the definition of active areas of said columns of said matrix of non-volatile memory cells and the definition of said field oxide zones, subsequent steps for the definition of the lines of said matrix of non-volatile memory cells, and a following step for the definition of said source lines.

Abstract: In a trench-gated MOSFET, a lightly doped drift region of the N-type drain lies in the mesa between the trenches. The gate is doped with N-type material so that depletion regions are formed in the drift region when the gate voltage is equal to zero. The depletion regions merge at the center of the mesa, pinching off the flow of current when the device is turned off. This current-pinching effect allows the P-type body region to be made shallower and doped more lightly than usual without creating a punchthrough problem, because the barrier represented by the depletion regions adds to the normal current blocking capability of the PN junction between the body and drain regions. When the device is turned on by biasing the gate to a positive voltage, a low resistance accumulation layer forms in the drift region adjacent the trenches.

Abstract: This method of fabricating a gate-control electrode (28) for an insulated-gate bipolar transistor, from a plate of electrically conducting material which is covered with an electrically insulating layer (22) and, on one of its large faces, delimits a connection pad intended to be soldered to the gate, includes the steps consisting in, on the pad, forming an electrically conductive layer (30) covering the electrically insulating layer (22), on the plate, forming an electrically conductive track for supplying the connection pad, and burying the supply track.

Abstract: A method for manufacturing a device of silicon carbide (SiC) and a single crystal thin film, which are wide band gap semiconductor materials and can be applied to semiconductor devices such as high power devices, high temperature devices, and environmentally resistant devices, is provided by heating a silicon carbide crystal in an oxygen atmosphere to form a silicon (di)oxide thin film on a silicon carbide crystal surface, and etching the silicon (di)oxide thin film formed on the silicon carbide crystal surface to prepare a clean SiC surface. The above SiC device comprises a clean surface having patterned steps and terraces, has a surface defect density of 108 cm−2 or less, or has at least a layered structure in which an n-type silicon carbide crystal is formed on an n-type Si substrate surface.

Abstract: The collector (anode) of a non punch through IGBT formed in a float zone silicon monocrystaline wafer is formed with a DMOS top structure and is thereafter ground at its bottom surface to a less than 250 micron thickness. A shallow P type implant is then made in the bottom surface and the wafer is then heated in vacuum to about 400° C. for about 30 to 60 seconds to remove moisture and other contaminants from the bottom surface. An aluminum layer is then sputtered on the bottom surface, followed by other metals to form the bottom electrode. No activation anneal is necessary to activate the weak collector junction.

Abstract: A MOS-gated power device includes a plurality of elementary functional units, each elementary functional unit including a body region of a first conductivity type formed in a semiconductor material layer of a second conductivity type having a first resistivity value. Under each body region a respective lightly doped region of the second conductivity type is provided having a second resistivity value higher than the first resistivity value.

Abstract: A method for manufacturing a device of silicon carbide (SiC) and a single crystal thin film, which are wide band gap semiconductor materials and can be applied to semiconductor devices such as high power devices, high temperature devices, and environmentally resistant devices, is provided by heating a silicon carbide crystal in an oxygen atmosphere to form a silicon (di)oxide thin film on a silicon carbide crystal surface, and etching the silicon (di)oxide thin film formed on the silicon carbide crystal surface to prepare a clean SiC surface. The above SiC device comprises a clean surface having patterned steps and terraces, has a surface defect density of 108 cm−2 or less, or has at least a layered structure in which an n-type silicon carbide crystal is formed on an n-type Si substrate surface.

Abstract: A method of manufacturing a semiconductor component includes providing a semiconductor substrate (200) having top and bottom surfaces, forming a drain electrode (160) at the bottom surface of the semiconductor substrate (200), and simultaneously forming source and gate electrodes (251, 254, 255, 253) at the first surface of the semiconductor substrate (200).

Abstract: An initial layer of an epitaxial layer is formed on an n+ type semiconductor substrate in which a crystal plane of a substrate surface is (100) plane and a crystal plane of its orientation flat is {100} plane. Then, a silicon oxide film having a film thickness of 400 to 600 Å is formed on a surface of the initial layer by thermal oxidization, and a silicon nitride film which functions as a mask for preventing the growth of oxide film and has a film thickness of 600 to 1000 Å is allowed to grow on the silicon oxide film by CVD process and then, is selectively dry etched to form an n− type epitaxial layer in which an initial groove is formed. Next, an inner surface of the groove is thermally oxidized at the oxidization temperature of 1100 to 1200° C. using the nitride film as a mask, and if an LOCOS oxide film having a film thickness of 0.6 to 0.8 &mgr;m is formed, the initial groove becomes a U-shaped groove.

Abstract: A MOS gated device is resistant to both high radiation and SEE environments. Spaced, N-type body regions are formed in the surface of a P-type substrate of a semiconductor wafer. P-type dopants are introduced into the surface within each of the channel regions to form respective source regions therein. The periphery of each of the source regions is spaced from the periphery of its respective channel region at the surface to define N-type channel regions between the spaced peripheries. A layer of gate oxide is formed over the channel areas. A doped polysilicon gate electrode is formed atop the gate oxide. A source electrode is formed atop the source regions. The MOS gated device is optimized to maintain a threshold voltage of between -2V to -5V for a total irradiation dose of 300 Krad while maintaining SEE withstand capability.

Abstract: An electronic semiconductor device (20) with a control electrode (19) consisting of self-aligned polycrystalline silicon (4) and silicide (12), of the type in which said control electrode (19) is formed above a portion (1) of semiconductor material which accommodates active areas (9) of the device (20) laterally with respect to the electrode, has the active areas (9) at least partially protected by an oxide layer (10) while the silicide layer (12) is obtained by means of direct reaction between a cobalt film deposited on the polycrystalline silicon (4) and on the oxide layer (10). (FIG.

Abstract: A structural enhancement to a conventional DMOS process flow addresses the well-known destructive latch up problem. The additional steps include a symmetric "deep" punch-through stopper implant and additional thermal budget to remove silicon damage and distribute the ionized dopants appropriately. The purpose of the implant is to create a low resistance base region within the parasitic bipolar transistor to prevent the device from activating under high current conditions. In terms of circuit characteristics, the goal is to lower the voltage drop at node Vx in FIG. 1C during avalanche breakdown. This structure also provides a means of suppressing the phenomena of punch-through breakdown which can also lower the device's voltage reading.

Abstract: In an insulated gate type field effect transistor and a manufacturing method of the same, a diffusion region is formed in a semiconductor substrate under an oxidizing atmosphere by thermal diffusion, and a first conductivity type semiconductor layer is formed on the semiconductor substrate by vapor-phase epitaxy after the formation of the diffusion region. Thereafter, the surface of the semiconductor layer is flattened, and a gate insulating film and a gate electrode are formed on the flattened semiconductor layer. Further, a well region as well as a source region are formed in the semiconductor layer to form an insulated gate type field effect transistor. As the surface of the semiconductor layer in which the insulated gate type field effect transistor is formed is flattened, even if the embedded region is formed in the wafer, the gate-source insulation withstand voltage characteristic can be prevented from being deteriorated.

Abstract: A method for producing a low-impedance contact between a metallizing layer and a semiconductor material of a first conductivity type having a semiconductor surface, an insulation layer on the semiconductor surface and a semiconductor layer on the insulation layer, includes applying a first insulating layer with a predetermined content of dopants on the semiconductor layer, and structuring the first insulating layer by anisotropic etching, forming first and second openings. The semiconductor layer is anisotropically etched by using the first insulating layer as a mask. A first dopant of a second conductivity type is implanted and driven through the first opening into the semiconductor material with a first phototechnique, forming a first zone in the semiconductor material. A second dopant of the first conductivity type is implanted through the second opening into the semiconductor material with a second phototechnique. A second doped insulating layer is applied over the entire surface.

Abstract: A lateral gate, vertical drift region transistor including a drain positioned on one surface of a substrate and a doped structure having a buried region therein positioned on the other surface of the substrate. The buried region defining a drift region in the doped structure extending vertically from the substrate and further defining a doped region in communication with the drift region and adjacent the surface of the doped structure. A source positioned on the doped structure in communication with the doped region and an implant region positioned in the doped region adjacent the surface and in communication with the source and buried region. An insulating layer positioned on the doped structure with a metal gate positioned on the insulating layer so as to define an inversion region in the implant region extending laterally adjacent the control terminal and communicating with the drift region and the source.

Abstract: In a method for forming a silicon carbide vertical FET, a first mask and a second mask that overlaps the first mask are used so that a first conductivity type impurity region is defined by one end of a certain portion of the first mask, and that portion of the first mask and the second mask are then removed so that a second conductivity type impurity region is defined by another portion of the first mask. Thus, the first conductivity type impurity region and the second conductivity type impurity region are positioned relative to each other, with respect to the first mask. If a mask including a tapered end portion is used, and ion implantation is conducted with different accelerating-field voltages, the first conductivity type region and the second conductivity type region may be formed by self-alignment, using only one mask. By controlling the impurity concentration of the channel region, the threshold voltage can be controlled, and a normally-off type FET can be provided.

Abstract: A semiconductor device (10) is formed in a semiconductor substrate (11) and an epitaxial layer (14). The semiconductor device includes a p-type body region (16), a source region (17), a channel region (19), and a drain region (102) formed in the epitaxial layer (14). Doped regions (20,22) are formed in the epitaxial layer (14) that contain dopant of a conductivity type that is opposite to the epitaxial layer (14). The doped regions (20,22) divide the epitaxial layer (14) to provide or define doped regions (21,23). The doped regions (20,22) are formed from a plurality of doped regions (30,31,32,33) that can be formed with high energy implants.

Abstract: A fabrication method for high voltage power devices with at least one deep edge ring includes the steps of growing a lightly doped N-type epitaxial layer on a heavily doped N-type substrate, growing an oxide on the upper portion of the epitaxial layer, masking and then implanting boron ions, etching the oxide to expose regions for aluminum ion implantation, forming a layer of preimplantation oxide, masking of the body regions with a layer of photosensitive material and implanting aluminum ions, and a single thermal diffusion process forming a layer of thermal oxide on the epitaxial layer and simultaneously forming at least one deep aluminum ring and an adjacent body region doped with boron.

Abstract: An MOS-gated power semiconductor device is formed by a process in which a self-aligned device cell is formed without any critical alignments. A sidewall spacer is used to mask the etching of a depression in the silicon to reduce the number of critical alignment steps. An optional selectively formed metal connects the polysilicon layer to the P+ and N+ diffusion regions. The sidewall spacer, in combination with the selectively formed metal, prevents impurities from diffusing to the parasitic DMOS channels and inverting them to cause leakage. A termination structure may also be formed by this process.

Abstract: A process for the manufacturing of an integrated circuit having DMOS-technology power devices and non-volatile memory cells provides for forming respective laterally displaced isolated semiconductor regions, electrically insulated from each other and from a common semiconductor substrate, inside which the devices will be formed; forming conductive gate regions for the DMOS-technology power devices and for the memory cells over the respective isolated semiconductor regions. Inside the isolated semiconductor regions for the DMOS-technology power devices, channel regions extending under the insulated gate regions are formed. The channel regions are formed by an implantation of a dopant along directions tilted of a prescribed angle with respect to a direction orthogonal to a top surface of the integrated circuit, in a dose and with an energy such that the channel regions are formed directly after the implantation of the dopant without performing a thermal diffusion at a high temperature of the dopant.

Abstract: Methods of forming power semiconductor devices include the steps of forming an insulated gate electrode on a face of semiconductor substrate containing a body region of first conductivity type (e.g., P-type) therein extending to the face. Using the gate electrode as a mask, a step is then performed to oxidize the body region and substrate at the face to form a first oxide layer. Source and drain region dopants are then implanted through the first oxide layer and into the body region and substrate to define recessed source and drain regions of second conductivity type therein, respectively. The step of implanting source and drain region dopants may be preceded by the step of etching the first oxide layer using an etching mask which covers the gate electrode. The step of oxidizing the body region and substrate may also be preceded by the step of forming nitride spacers on sidewalls of the gate electrode and then also using the nitride spacers as a mask during the oxidation step.

Abstract: A vertical SiC trench MOSFET power switching FET includes a gate electrode in the trench. The MOSFET adds a buried region of a first conductivity type, more heavily doped than a base layer of the first conductivity type, to the base layer except adjacent to the trench. The buried region is preferably disposed in the base layer, or between a drift layer of a second conductivity type and the base layer. The region of the first conductivity type is optionally disposed below the bottom of the trench to encourage expansion of the depletion layer of the MOSFET. A depletion-type vertical SiC MESFET of the invention includes a buried region of the first conductivity type in a base layer of a second conductivity type. A Schottky electrode on a portion of the base layer above the buried region ensures adequate expansion of a depletion layer.

Abstract: A two-terminal current limiting component, includes a substrate of a first conductivity type; separated wells of the second conductivity type; a first annular region of the first conductivity type in each well; a second annular region of the first conductivity type having a low doping level between the periphery of each first annular region and the periphery of each well; an insulating layer over the second annular region and the surface portions of the substrate; a first metallization coating the upper surface of the component; and a second metallization coating the lower surface of the component.

Abstract: A high-speed MOS-technology power device integrated structure includes a plurality of elementary functional units formed in a lightly doped semiconductor layer of a first conductivity type, the elementary functional units including channel regions of a second conductivity type covered by a conductive insulated gate layer including a polysilicon layer; the conductive insulated gate layer also including a highly conductive layer superimposed over the polysilicon layer and having a resistivity much lower than the resistivity of the polysilicon layer, so that a resistance introduced by the polysilicon layer is shunted with a resistance introduced by the highly conductive layer and the overall resistivity of the insulated gate layer is lowered.

Abstract: A power MOSFET (Metal Oxide Semiconductor Field Effect Transistor) device formed on a semiconductor substrate having a body region of a first conductivity type diffused in a semiconductor substrate with an epitaxial layer of a second conductivity type. There is also a source region of a second conductivity type formed in the body region. A portion of the body region adjacent to the source region is compensated by ion implanting a material of the second conductivity type in the portion of the body region such that the impurity concentration of the body region at the portion is reduced. As a consequence, with reduced impurity charge in the body region adjacent to the source, the threshold voltage of the MOSFET device is lowered but at no comprise in punch-through tolerance because the reduction in charge is remote from the origin of the depletion layer which is located at the boundary between the body region and the epitaxial layer.

Abstract: An insulated gate field effect transistor is manufactured according to a process in which an insulated gate structure is formed along a semiconductor chip. Dopant is introduced into the chip to form a body region, semiconductor material outside the body region forming a drain region. Dopant is introduced into the chip at the location of part of the body region to form a source region spaced apart from the drain region by a channel region. Dopant of the same conductivity type as the body-region dopant is introduced through a dopant-introducing section of the chip's upper surface and into the chip at the location of part of the body region to form a sub-surface peaked portion of the body region, the dopant-introducing section being spaced laterally apart from the channel and source regions. The sub-surface peaked portion reaches a peak net dopant concentration below the chip's upper surface so as to improve the transistor's ruggedness under drain avalanche conditions.

Abstract: A semiconductor device manufacturing process is disclosed in which one processing step is reduced by replacing the photoresist film conventionally used for masking in the formation of the heavily doped n-type layer by an oxide film, and by monitoring, in the monitor region, the simultaneous formation of the contact holes in the oxide films different in the respective thickness thereof. An n+ region is formed by using a second insulation film and a polysilicon gate electrode formed on a semi-conductor wafer as masks for implanting arsenic ions. Further, a contact hole to be formed on a p-type region covered with a fourth insulation film and a second insulation film and a contact hole to be formed on the n+ region covered with the fourth insulation film are formed simultaneously under the monitoring of the formation of the contact holes in a monitor region.

Abstract: A VDMOS structure with an added n- doping component, and a LOCOS oxide self-aligned to it, at the surface extension of the drain. The additional shallow n- component permits the body diffusion to be heavier, and hence reduces the risk of latchup.

Abstract: A method for producing a semiconductor device having a semiconductor layer of SiC is disclosed. The method comprises the steps of applying an insulation layer on the semiconductor layer, implanting first impurity dopant into the semiconductor layer, and annealing this layer at at least about 1500.degree. C. so that the implanted first impurity dopant is activated, wherein the insulating layer comprises AlN as a major component and the insulating layer is applied before the annealing step and maintained on the semiconductor layer during the annealing step.

Abstract: A diffused channel insulated gate field effect transistor comprised of a gate isolation layer and a gate electrode positioned on an upper surface of a semiconductor substrate of a first conductivity type; a body region of a second conductivity type present in the semiconductor substrate lying below a part of the gate electrode, on at least one side thereof, and extending downwards to a first depth; a source region of said first conductivity type present in the body region, spaced away from the first end of the gate electrode, at the upper surface and extending downwards therefrom to a second depth, shallower than the first depth; and a lightly doped region of the first conductivity type present in the body region, at least partly between the source region and the gate electrode, extending downwards to a substantially shallower depth than the second depth.

Abstract: A semiconductor device includes a substrate (11), a first region (21) in the substrate (11) wherein the first region (21) has a first conductivity type, a second region (22) in the substrate (11) wherein the second region (22) is adjacent to the first region (21) and wherein the second region (22) has a second conductivity type different from the first conductivity type, and a third region (24) in the substrate (11) wherein the third region (24) overlaps the first and second regions (21, 22) and wherein the third region (24) has a damaged crystalline structure.

Abstract: A source cell having reduced area and reduced polysilicon window width requirements for use as the source region in a DMOS transistor is disclosed, comprising: a source region of semiconductor material disposed on a semiconductor substrate; a plurality of backgate contact segments of predetermined size and separated by predetermined distances; and a plurality of source contact windows alternating with the backgate contact segments so that a narrow source contact region is formed of alternating source contact and backgate contact material. A DMOS transistor embodying the source region including the backgate contact segments and windowed source contacting regions of the invention is disclosed. An integrated circuit providing an array of DMOS transistors having the improved source regions of the invention is disclosed.Other devices, systems and methods are also disclosed.

Abstract: An integrated structure active clamp for the protection of a power device against overvoltages includes a plurality of serially connected diodes, each having a first and a second electrode, obtained in a lightly doped epitaxial layer of a first conductivity type in which the power device is also obtained; a first diode of said plurality of diodes has the first electrode connected to a gate layer of the power device and the second electrode connected to the second electrode of at least one second diode of the plurality whose first electrode is connected to a drain region of the power device; said first diode has its first electrode comprising a heavily doped contact region of the first conductivity type included in a lightly doped epitaxial layer region of the first conductivity type which is isolated from said lightly doped epitaxial layer by a buried region of a second conductivity type and by a heavily doped annular region of the second conductivity type extending from a semiconductor top surface to said bu

Abstract: A method for forming a semiconductor device includes forming insulated gate regions (122,222) on a substrate (26) using a first photo-masking step, forming a base region (47) through an opening (143) between the insulated gate regions (122,222), and forming a source region (152) within the base region (47). Next, a protective layer (61) is formed and selectively patterned using a second photo-masking step to form an opening (62) within the first opening (143) and an opening (63) above one of the insulated gate regions (122). Next, a portion (66) of the substrate (26) and a portion (67) of the insulated gate region (122) are removed. Ohmic contacts (74,76) are then formed and patterned using a third photo-masking step. Additionally, a termination structure (81) is described.

Abstract: A manufacturing process for an integrated circuit which includes at least one vertical-current-flow MOS transistor. The patterned photoresist which screens the body implant is also used to mask the etching of a nitride layer over a pad oxide. After the photoresist is cleared, the nitride pattern is transferred into the oxide, and the resulting oxide/nitride stack is used to mask the source implant. The nitride/oxide stack is then removed, the gate oxide is grown, and the gate layer is then deposited.