Abstract: Disclosed is a high breakdown voltage semiconductor device comprising a semiconductor substrate, an active layer consisting of a high resistivity semiconductor layer of a first conductivity type formed on the substrate with an insulating layer interposed therebetween, a first impurity region of the first conductivity type formed within the active layer, a second impurity region of a second conductivity type formed within the active layer, a third impurity region of the second conductivity type formed within the second impurity region and having a high impurity concentration, a first electrode being in ohmic contact with the first impurity region and the fourth impurity region, and a second electrode being in Schottky contact with the second impurity region and in ohmic contact with the third impurity region.

Abstract: In a CMOS circuit including a source diffusion layer and a well region which are at the same potential, a P.sup.+ -type source diffusion layer and an N.sup.+ -type substrate diffusion layer are formed in a portion corresponding to a source region in a surface area of an N-type well region. A source contact is formed on the source and substrate diffusion layers through a salicide layer to connect the diffusion layers to their upper wiring layer. Since, therefore, the source contact can be arranged closer to a P-type well region, the layout area can be reduced.

Abstract: Improved power MOSFET structure, and fabrication process are disclosed in this invention to achieve cost savings by simplified device structure and fabrication processes, and also by reducing the required die size. Specifically, in a novel MOSFET device, insulation of mobile ions are achieved by extending the poly gate and metal contacts such that the passivation layer is no longer required and the fabrication process is simplified such that the MOSFET device can be manufactured at a lower price. Furthermore, in another MOSFET device, the gate runner is used to replace the field plate such that the requirement of a field plate as that in a conventional MOSFET device is also eliminated and, by reducing the die size, the cost of manufacture is further reduced.

Abstract: A semiconductor device includes a first transistor (52) and gated diode (50) formed at a face of a semiconductor layer (56). The first transistor (52) includes a source region (60a), a drain region (60b), a gate oxide layer (62), and a conductive gate (64). The gated diode (54) includes a first moat region (66a), a second moat region (66b), a gate oxide layer (68), and a conductive gate (70). A first conductor (77) connects the conductive gate (70) of the gated diode (54) to the semiconductor layer (56) and a second conductor (76) connects the moat regions (66a, 66b) of the gated diode (54) to the conductive gate (64) of the first transistor (52). Gated diode (54) has a reduced breakdown voltage relative to the gate oxide layer (62) of first transistor (52) and thus establishes a leakage path to semiconductor layer (56) to direct leakage current to semiconductor layer (56), thereby inhibiting charge from accumulating on the gate oxide layer (62) of first transistor (52).

Abstract: Semiconductor device with a semiconductor cathode having an emissive part (pn junction) separated from a contact part which has locations at which a controlled breakdown occurs on a contact part metallization at excessive voltages, so that, during manufacture and operation, the emissive part in an election tube is protected from damage.

Abstract: An electrostatic discharge (ESD) protection circuit includes diodes connected in series back-to-back between the signal input and power supply terminals of the circuit to be protected. This allows the input signal to rise a selected distance above the supply voltage without triggering the ESD protection circuit. The ESD protection circuit can be fabricated in integrated form, with the diodes including a pair of P+ regions in an N-well or separate P+ regions forming PN junctions with separate N-wells. The diodes may also be formed in a layer of polysilicon over a field oxide region. Optionally, a second pair of back-to-back diodes can be connected between the signal input terminal and ground. This permits the input signal to fall a selected distance below ground without triggering the ESD protection circuit.

Abstract: An N.sup.- - region is formed by diffusion on a P- semiconductor substrate, and a P- region is formed in a surface portion of the N.sup.- - region. A P.sup.+ - region is formed in an outer peripheral portion of the N.sup.- - region, to suppress expansion of a depletion layer of the P- semiconductor substrate when a high voltage is applied. A gate oxide film is formed on the semiconductor substrate, and a gate electrode of polycrystalline silicon is formed on the gate oxide film, particularly on a channel region which is formed by the semiconductor substrate and the P.sup.+ - region, which is as a whole the same as a structure of a lateral N-channel MOSFET. Circuit elements are formed within the N.sup.- - region, and a high voltage is applied. Circuit portions are isolated as the gate electrode and a source region are grounded. This reduces the number of steps for manufacturing a high-insulation IC, increases a breakdown voltage, and integrates the circuit denser.

Abstract: A lateral thin-film Silicon-On-Insulator (SOI) device includes a semiconductor substrate, a buried insulating layer on the substrate and a lateral MOS device on the buried insulating layer and having a source region of a first conductivity type formed in a body region of a second conductivity type opposite to that of the first. A lateral drift region of a first conductivity type is provided adjacent the body region, and a drain region of the first conductivity type is provided laterally spaced apart from the body region by the drift region. A gate electrode is provided over a part of the body region in which a channel region is formed during operation and over at least a part of the lateral drift region adjacent the body region, with the gate electrode being insulated from the body region and drift region by an insulation region.

Abstract: Disclosed is a high breakdown voltage semiconductor device comprising a semiconductor substrate, an active layer consisting of a high resistivity semiconductor layer of a first conductivity type formed on the substrate with an insulating layer interposed therebetween, a first impurity region of the first conductivity type formed within the active layer, a second impurity region of a second conductivity type formed within the active layer, a third impurity region of the second conductivity type formed within the second impurity region and having a high impurity concentration, a first electrode being in ohmic contact with the first impurity region and the fourth impurity region, and a second electrode being in Schottky contact with the second impurity region and in ohmic contact with the third impurity region.

Abstract: A high voltage semiconductor device having an improved junction termination extension for increasing the surface breakdown junction voltage. The device comprises a semiconductor substrate (10) of a first electrical conductivity type having a major surface (24) with an edge (26). The substrate has a first impurity region (22) of a second electrical conductivity type formed therein and having a first doping concentration and a second impurity region (28) of a said second electrical conductivity type, having a second doping concentration less than the first doping concentration, formed in the substrate between the first impurity region and the edge, and a field shield plate (30) disposed on the major surface in conductive relation with the first impurity region. The first field shield plate has an outer edge which terminates above the second impurity region.

Abstract: In a first region of a semiconductor substrate, there are formed MIS transistors each composed of a gate insulating film, a gate electrode, and source/drain regions. In a second region of the semiconductor substrate, there is formed an impurity diffusion layer serving as a conductive layer. On an interlayer insulating film, there are formed an antenna interconnection connected to the gate electrodes and an interconnection for charge dissipation connected to the conductive layer. During the process of dry etching for forming the interconnections, charges move into the semiconductor substrate via the interconnection for charge dissipation. The deterioration of the gate insulating film caused by the injection of charges into the gate electrode is suppressed and the degradation of characteristics of the MIS transistor including a shift in threshold is also suppressed.

Abstract: A high breakdown voltage pch-MOSFET having a breakdown voltage of 150 V or more and a control element controlling the same are formed in a common n.sup.- epitaxial layer. Only an n-type region of n.sup.- epitaxial layer is distributed at a region located between the high breakdown voltage pch-MOSFET and the control element and extending along the substrate surface. A semiconductor device thus formed achieves a good throughput and reduces a required chip area.

Abstract: The invention relates to a high voltage integrated circuit with connecting metal conductors (30, 32) connected to ground or potential near ground and covered by a passivating layer (18). The invention is characterized by said passivating layer (18) being partially broken up above said metal conductors to prevent activation of parasitic MOS-transistor.

Abstract: By providing a semiconductor device such as a cold cathode (7) with extra zener or avalanche structures (26, 27 and 32, 33, respectively) a robust structure is obtained which is resistant to damage during manufacture and use of a vacuum tube. The semiconductor zones (26, 27, 32, 33) are thus also utilized for realizing electron optics (particle optics).

Abstract: It is an object to provide a semiconductor apparatus having improved dielectric breakdown strength characteristics both by eliminating the discontinuity caused to the interface between a semiconductor layer and the overlying insulator film on account of the FLR provided for increasing the dielectric breakdown strength and by preventing the redistribution of impurities from the FLR into the insulator film. Another object is to provide a process for fabricating such improved semiconductor apparatus. The semiconductor layers of a first conduction type (i.e., n.sup.- type semiconductor layer 1b and epitaxial layer 1c) are provided with the semiconductor region of a second conduction type (i.e., p-type base region 2) to form a semiconductor device (transistor) and FLRs 4a and 4b are provided external to the perimeter of said semiconductor region but without being exposed from the surface of the epitaxial layer 1c.

Abstract: An image sensor includes a substrate on which a light-receiving element and a thin-film transistor for transferring an output from the light-receiving element are formed, and a silicon integrated circuit chip for driving the thin-film transistor and processing signals. All externally connected input/output signal lines are extracted through or electrical connections to the silicon integrated circuit chip.

Abstract: A semiconductor device having: a semiconductor substrate of a first conductivity type; a well formed in a surface of said semiconductor substrate, the welt being of a second conductivity type opposite to the first conductivity type; a first MOS transistor formed in a surface of a first conductivity type region of the semiconductor substrate; a second MOS transistor formed in a surface of the well; a wiring connected to the gate electrodes of the first and second MOS transistors; and a protection diode with a p-n junction formed in the first conductivity type region and comprising a second conductivity type region electrically connected to the wiring and the first conductivity region of the semiconductor substrate, wherein the wiring and the well are not directly connected electrically. A CMOS type semiconductor integrated circuit device with a long and wide area wiring is realized which can effectively suppress damage to a gate oxide film of a MOSFET.

Abstract: A field shield element for isolating semiconductor devices formed on a common substrate. The field shield element comprises an electrode of a high melting point metal which may have a reduced thickness and which avoids punch through of a connection point through the field shield electrode during manufacture. By employing the shield gate electrode metal having a high melting point, the reduction in thickness of the shield gate electrode provides a corresponding reduction in thickness of the offset existing between the semiconductor device and the isolation structure formed with the field shield element. The shield gate electrode may be combined with metal silicon compounds, and metal nitrides to realize the foregoing benefits of avoiding punchthrough and reducing the offset.

Abstract: A high withstand voltage transistor and a method for manufacturing the same are disclosed. The transistor includes a semiconductor substrate, a field oxide film, a channel region formed of first and second channel regions each having a different concentration level, a gate insulating film having a step difference, a gate electrode having a step difference, a drain region including first, second, and third impurity regions, a source region including first and third impurity regions, a spacer, an interlayer dielectric film and a metal electrode. Threshold voltage can be maintained to an appropriate level, junction break voltage can be increased, and the punchthrough characteristic can also be enhanced.

Abstract: A monolithic IGBT and control circuit therefor are integrated into a common chip. The IGBT is formed in a first area of the chip and the control circuit is formed in a second laterally spaced area and in a P well. Means are provided to prevent hole injection from the P.sup.+ substrate into the P well during IGBT operation. The means includes a sufficient spacing between the areas; a P.sup.+ collection region between the areas or an N.sup.+ diffusion between the areas which is connected to the P.sup.+ substrate. The areas are surrounded by a common field termination structure which, however, leaves a small surface bridge between the two areas. Control conductors from the control area to the IGBT area cross over the narrow area, and not over the field terminations. A lateral PNP transistor which is integrated in the chip and is external of the IGBT area is connected to the central N.sup.

Abstract: A semiconductor device including a substrate having a first conductivity type on which are formed first and second epitaxial layers of the same conductivity type of the substrate. The semiconductor device also includes a first diffused region having a second conductivity type formed in a first portion of the first and second epitaxial layers. Said first diffused region defines a first junction with said first and second epitaxial layers. The semiconductor device also comprises an edge structure having the second conductivity type formed in a second portion of the first and second epitaxial layers. The edge structure includes a second diffused region having the second conductivity type formed in the first and second epitaxial layers, said second diffused region defining a second junction with said first and second epitaxial layers.

Abstract: A high-voltage lateral field effect transistor has a lightly doped n-type extended drain region depleted by depletion layers extending from a p-n junction between the lightly doped n-type extended drain region and a p-type silicon substrate and a p-n junction between the lightly doped extended drain region and a p-type impurity region formed in a surface portion thereof, and an n-type step-down region contiguous with the lightly doped n-type extended drain region is formed in a surface of the p-type impurity region so as to permit a step-down drain voltage lower than the drain voltage to be transmitted therefrom, thereby preventing damage to a gate insulating layer of a field effect transistor.

Abstract: A FET including a channel region and a drift region in a channel layer with a source in the channel region and a drain in the drift region. The current channel between the source and drain defining a straight transistor portion and a curved transistor portion. An oxide with a thin portion overlying the channel region and a thick portion overlying the drift region, and a gate on the thin oxide overlying the current channel. A drain field plate and a gate field plate on the thick oxide with spaced apart edges and a damaged region underlying the edges of the field plates only in the curved transistor portion to reduce electric fields at the edges of the field plates. Also, the current channel has a greater length and the edges are spaced apart farther in the curved transistor portions.

Abstract: An image sensor includes a substrate on which are formed a light-receiving element and a thin-film transistor for transferring an output from the light-receiving element, and a silicon integrated circuit chip for driving the thin-film transistor and processing signals. All externally connected input/output signal lines are extracted through or electrically connected to the silicon integrated circuit chip.

Abstract: A high breakdown voltage semiconductor device comprising a semiconductor substrate, an insulating layer formed on the semiconductor substrate, an active layer formed on the insulating layer and made of a high resistance semiconductor of a first conductivity type, a first impurity region of the first conductivity type formed in the active layer, and a second impurity region of a second conductivity type formed in the active layer and spaced apart from the first impurity region by a predetermined distance. The first impurity region is formed of diffusion layers. The diffusion layers are superimposed one upon another and differ in diffusion depth or diffusion window width, or both.

Abstract: A power integrated circuit device with multiple guard rings and field plates overlying regions between each of the guard rings. Each of the field plates form overlying a dielectric layer also between each of the guard rings. Multiple field plates can exist between each of such guard rings. At least one field plate couples to a main junction region, and another field plate couples to a peripheral region, typically a scribe line. The present power device structure with multiple guard rings and field plates provides a resulting guard ring structure which allows for such device to achieve higher voltage applications.

Abstract: A BiCMOS process where a base region is formed in a relatively highly doped n-type substrate region. Boron is implanted at two different energy levels to form the base region and a counter doped n region near the base collector junction to prevent impact ionization.

Abstract: A semiconductor integrated circuit comprises a semiconductor substrate of a first conductivity type, at least one electrically erasable floating gate type semiconductor non-volatile memory transistor disposed on a surface of the semiconductor substrate, a well region of a second conductivity type formed in the surface of the semiconductor substrate, and a program voltage switching transistor of the first conductivity type disposed in the well region. A field insulation film is disposed on the surface of the semiconductor substrate. A field dope region of the first conductivity type is provided beneath the field insulation film. The field dope region preferably has an impurity concentration higher than an impurity concentration of the semiconductor substrate. By this construction, current leakage is prevented at the time when a high voltage occurs such as, for example, when performing a writing operation with respect to EEPROM.

Abstract: By providing a semiconductor device such as a cold cathode (7) with extra zener or avalanche structures (26, 27 and 32, 33, respectively) a robust structure is obtained which is resistant to damage during manufacture and use of a vacuum tube. The semiconductor zones (26, 27, 32, 33) are thus also utilized for realizing electron optics (particle optics).

Abstract: The breakdown characteristics of a lateral transistor integrated in an epitaxial layer of a first type of conductivity grown on a substrate of an opposite type of conductivity and comprising a drain region formed in said epitaxial layer, are markedly improved without recurring to critical adjustments of physical parameters of the integrated structure by forming a buried region having the same type of conductivity of the substrate and a slightly higher level of doping at the interface between the epitaxial layer and the substrate in a zone laying beneath the drain region of the transistor.

Abstract: A semiconductor structure having one or a plurality of lateral, high-blocking semiconductor components in a semiconductor of a metalized substrate (2), a dielectric layer (3) contiguous to the substrate, a homogeneously doped drift zone (4) disposed above the dielectric layer, and having heavily-doped zones of the semiconductor components which are formed in or extend into the drift zone and are electrically contacted. At least the zones (5, 6) of the semiconductor components, which can have a high potential difference with respect to the substrate during operational functioning mode of the semiconductor components, extend up to the dielectric layer (3).

Abstract: A semiconductor device which allows an ON-state voltage to be lower than that of a conventional device and a method of manufacturing such a device. In this semiconductor device, a gate electrode is formed to have a planar area of its region covering a first base layer larger than that of its region covering a second base layer, thereby increasing a cathode short-circuit ratio of a cathode-shorted diode equivalent to this semiconductor device. As a result, a lower voltage than conventional ON-state can be obtained.

Abstract: A termination structure for a MOSgated device uses a plurality of series-connected lateral P-MOS devices extending in series, from source to drain of the main device. The P-MOS devices are formed in ring fashion around the periphery of the area being terminated. A plurality of concentric spaced P rings diffused into an N type chip termination area are covered by the main device gate oxide which is, in turn, covered with conductive polysilicon to act as a gate for the P-MOS devices so formed. The innermost P ring of each pair of P rings is connected to its gate to prevent turn on of the N channel device. The breakdown voltage of the termination is the sum of the threshold voltage of the P-MOS transistors. A zener diode can be added to the chain to increase the breakdown voltage of the termination.

Abstract: A semiconductor device characterized by a field limiting ring formed by a number of field limiting cells that define wells which are laterally diffused to form a continuous equipotential ring between interior and exterior regions of a semiconductor device. A number of active cells are formed in the interior region, and are therefore delineated from the exterior region of the device. Each of these active cells is a transistor, and preferably a field-effect transistor, whose structure is essentially identical to the field limiting cells, except that their wells are not merged but instead are isolated from each other. The field limiting ring increases the breakdown voltage and the ruggedness of device, and therefore enables the device to sustain high voltages when the device is in the off-state. The process does not require masking, implanting and diffusion steps for the sole purpose of forming the field limiting ring, but is instead fully integrated with the semiconductor process for forming the active cells.

Abstract: There is disclosed a layout of a high voltage Darlington pair in which a circular field plate is utilized for both high voltage transistors in order to reduce the layout area. In this layout, both transistors of a Darlington pair are circular transistors and they both have a common center. This enables both high voltage transistors to share one field plate ring and one collector ring.

Abstract: An IGBT chip includes a unit cell region and a guard ring region which surrounds the unit cell region. In the unit cell region, a plurality of IGBT unit cells are formed, each of which comprises a base layer, a source layer, a common gate electrode, a common source electrode, and a common drain electrode. In the guard ring region, at least one diffused layer making up a guard ring is formed. Further, an annular diffused layer is formed and is connected to the drain electrode. The annular diffused layer is disposed away from the outermost guard ring by a specified length. This length is such that the punch-through occurs before the avalanche breakdown voltage of the junction associated with the outermost guard ring. Therefore, the withstand voltage against the avalanche breakdown when surge voltage is applied to the drain electrode is improved.

Abstract: The invention relates to a monolithically integrated semiconductor arrangement, where from the first main surface a first zone (p) and a second zone (n.sup.+) are diffused into a substrate (2), which is weakly doped (substrate region n.sup.-) under a first main surface (3) and is more strongly doped (substrate region n.sup.+) under a second main surface (4). An insulating passivation layer is attached to the first main surface (3), on top of which a metallic cover electrode (D) is located, which covers adjacent substrate regions (n.sup.-) and the edge areas of the first zone (p) and the second zone (n.sup.+). In accordance with the invention, at least one additional zone (.nu.) of the same type of conductivity as the associated zone (n.sup.+), but with weaker doping, is diffused in for increasing the break-through voltage, and is connected to the zone (n.sup.+), does not contact the other zone (p) and prevents the zone (n.sup.+) from directly bordering the substrate (n.sup.

Abstract: A phototransistor is provided with a first resistor that operates as a shunt and a second resistor that operates to protect the device from damage that could be caused by a reverse bias condition. The possible damage results from the creation of a PN junction relationship caused by the doping of N conductivity type material with P.sup.+ conductivity type material in order to form the first resistor. This junction relationship creates a parasitic diode that provides a current path between the emitter and collector terminals of the phototransistor. In order to prevent damage that might occur during a reverse voltage connection, a second resistor is connected between the emitter of transistor Q.sub.1 and the first resistor. The second resistor is in series with the junction relationship resulting from the structure used to form the first resistor and therefore serves to limit the current flowing between the emitter and collector terminals of the transistor under reversed bias conditions.

Abstract: The present invention provides a heat sink and electromagnetic interference shield assembly for a plurality of semiconductor elements. The semiconductor elements are connected with other circuit elements to form an electrical circuit. Each semiconductor element has a metal portion for dissipating heat generated by the semiconductor element. The metal portion also emits electrical energy as a result of the operation of the semiconductor element thereby causing unwanted electromagnetic interference. The assembly comprises an insulator attached to the meted portion of the semiconductor element and a substrate for mounting the plurality of semiconductor elements. The insulator is of a thermally conductive material to facilitate the conduction of thermal energy away from the semiconductor element. The substrate has a metal base layer, a middle insulating layer, and a plurality of metal mounting areas for mounting the plurality of semiconductor elements.

Abstract: A monolithic integrated semiconductor is proposed, in which on the main surface of a monolithically integrated n-p-n transistor or p-n-p transistor, a cover electrode (D1) is mounted for internal voltage limitation, covering only a single junction region between a highly doped zone (5) and the weakly doped substrate (1). An adjacent highly doped zone (4) is not covered by the cover electrode (D1). By connecting the metal cover electrode (D1) to the pickup (12) for a voltage divider (R1, R2), a breakdown voltage can be adjusted that is higher than the sum of the depletion breakdown voltage and the enhancement breakdown voltage.

Abstract: The present invention is primarily directed to obtaining a P channel high voltage transistor with an improved breakdown voltage. A first N type well region is provided in a main surface of a P type semiconductor substrate. A first field oxide film is provided in the main surface of the first N type well region. A P type source region and a P type drain region are provided on the opposite sides of the first field oxide film in the main surface of the first N type well region. A P type impurity injection region is provided immediately under the field oxide film so as to be connected to the P type drain region. A gate electrode is provided between the P type source region and the P type drain region on the first N type well region. An N.sup.+ ion injection region is provided between the P type source region and a channel in the N type well region. The first N type well region located under the P type drain region has its N type impurity concentration uniform at any depth.

Abstract: A trench gate lateral MOSFET structure has the voltage supported along side walls and the bottom surface of the trench. With narrow source and drain mesa regions that are optimally doped, a uniform electric field is obtained vertically in the mesa regions and horizontally at the bottom of the trench, allowing a relative high doping level in an N-drift region resulting in specific on-resistances well below those of conventional lateral MOSFETs at a high breakdown voltage.

Abstract: For a vertical DMOS power transistor or a high voltage bipolar transistor, an edge termination at the perimeter of the die surrounding the active transistor cells includes multiple spaced apart field rings. A trench is located between each adjacent pair of field rings and is insulated either by oxide formed on the sidewalls thereof or by an oxide filling. The insulated trenches allow the field rings to be very closely spaced together. Advantageously the trenches may be formed in the same process steps as are the trenched gate electrodes of the active portion of the transistor. This structure eliminates the necessity for fabricating thick field oxide underlying a conventional field plate termination, and hence allows fabrication of a transistor without the need for a field plate termination, and in which the multiple field rings are suitable for a transistor device having a breakdown voltage in the range of 20 to 150 volts.

Abstract: Semicondctor devices having a curved P-N junction in an active area of the device and an edge passivation region extending from the active area to an edge region of the device include an electrically resistive ribbon that spirals outwardly from the active area to the edge of the device so that a voltage difference between the active area and the edge region is spread along the length of the ribbon. The ribbon may take the form of a linear resistor or may include plural diodes. The distance between radially overlapping portions of the spiralling ribbon and the cross-sectional area of the ribbon may be varied to spread the equipotential lines in the device so as to reduce the effect of the curved P-N junctions on the breakdown voltage of the device.

Abstract: A high current, high voltage transistor which can be easily electrically stacked to extend the voltage range and uses less silicon area than a conventional stacked transistor configuration and a configuration of field plates that provide the greatest breakdown voltages with the highest ohmic values. Also, a star shaped field plate design which provides the greatest breakdown voltages with the highest ohmic values. The field plate is constructed using several concentric rings connected by fingers that are wider at towards the center of the concentric rings and narrower towards the perimeter of the concentric rings.

Abstract: A semiconductor device (12) with reduced high voltage termination area and high breakdown voltage. The device comprises first and second field shield plates (46), (48). The first field shield plate (46) is disposed above a high voltage first impurity region (22) and a junction extension doped region (42) and is in contact with a conductive material (26) which comprises the high voltage terminal of the device (12). A second field shield plate (48) is disposed above a low voltage second impurity region (30) and the junction extension doped region (42) and is covered by an extended portion (35) of a low voltage source contact (34).

Abstract: A Fermi-FET includes a Fermi-tub region at a semiconductor substrate surface, wherein the Fermi-tub depth is bounded between a maximum tub depth and a minimum tub depth. The Fermi-tub depth is sufficiently deep to completely deplete the Fermi-tub region by the substrate tub junction at the threshold voltage of the field effect transistor, and is also sufficiently shallow to produce a closed inversion injection barrier between the source region and the drain region below the threshold voltage of the Fermi-FET. High saturation current and low leakage current are thereby produced simultaneously. Source and drain injector regions and a gate sidewall spacer may also be provided.

Abstract: A semiconductor device of the RESURF type with a lateral DMOST (LDMOST), comprising a semiconductor body (1) of substantially a first conductivity type and a surface region (3) of a second conductivity type adjoining the surface (2). The LDMOST comprises a back gate region (5) of the first conductivity type provided in the surface region (3), with a source region (6) of the second conductivity type in the back gate region (5) and a channel region (7) defined between the source region (6) and an edge of the back gate region (5). A drain region (8) of the second conductivity type is at a distance from the back gate region (5). A number of breakdown voltage raising zones (9) of the first conductivity type are provided between the back gate region (5) and the drain region (8).

Abstract: The junction field effect transistors (JFETs) of this invention have improved breakdown voltage capability, reduced on-resistance and improved overdrive capability. The JFET on-resistance is decreased by ion-implanting an insulating layer covering a layer that contains the source and gate regions of the unipolar transistor. The charge of the implanted ions is the same as the charge polarity of the gate regions. To improve the overdrive capability of a JFET a region of conductivity opposite to the conductivity of the gate region is formed in the gate region of the transistor. This region of opposite conductivity creates another junction within the gate region i.e., the junction between the region of opposite conductivity and the gate region, and the junction between the gate region and the layer containing the gate region.

Abstract: There is provided a power semiconductor integrated circuit device without lowering a breakdown voltage of a pn junction located below a wiring layer to which a high voltage is applied. The device includes an N.sup.- -type semiconductor substrate which is provided with an N.sup.+ -type region and a P.sup.+ -type region to form, for example, a lateral diode. An insulating film is formed over the substrate surface, on which a wiring layer is provided so as to be connected to the N.sup.+ -type region and to pass over the P.sup.+ -type region. A film resistor connected between the N.sup.+ -type region and the P.sup.+ -type region is formed in the insulating film so as to be crossed by the wiring layer at least once.