Abstract: An IC card comprises: a plane coil having respective terminal sections; a semiconductor element arranged at a position not overlapping with the plane coil, the semiconductor element having electrode terminals; means for electrically connecting the respective terminal sections of the plane coil to the electrode terminals of the semiconductor element; and a reinforcing frame arranged on a face substantially the same as that of the semiconductor element so that the semiconductor element is surrounded by the reinforcing frame.

Abstract: In a high breakdown voltage semiconductor device, a buried diffusion region is formed on a semiconductor substrate and an epitaxial layer is formed on the buried diffusion region and the substrate. The epitaxial layer includes a low breakdown voltage element region adjoined by a high breakdown voltage isolation region. A method for forming the high breakdown voltage isolation region complies with a Resurf condition by adjusting a thickness and an impurity concentration of the epitaxial layer. Thus, a high breakdown voltage semiconductor device and a manufacturing process therefor is provided, which includes a low breakdown voltage element region and a high breakdown voltage element region, and a high breakdown isolation region separates a high breakdown voltage region without impairing the characteristics of an element formed on the low breakdown voltage element region.

Abstract: A method for forming a lateral DMOS transistor comprises: a) forming a first doped region of a first conductivity type in a semiconductor substrate of the first conductivity type; b) forming an epitaxial layer on the substrate; c) forming a second doped region of the first conductivity type in the epitaxial layer; and d) forming a body region of the first conductivity type in the epitaxial layer. The process of forming the first and second doped regions and the body region includes thermally diffusing dopants in these regions so that the first and second doped regions diffuse and meet one another. The body region also meets and contacts the second doped region. The body region is electrically coupled to the substrate via the first and second doped regions. Source and drain regions are then formed in the epitaxial layer. By forming the transistor in this manner, the electrical resistance between the body region and substrate can be reduced or minimized.

Abstract: A wide bandgap semiconductor single crystal is applied as a semiconductor substrate material of a semiconductor surge absorber, and a surge absorption operation starting voltage is set by a punchthrough of a pn junction, to obtain a semiconductor surge absorber with a repetitive operation and a high surge endurance.

Abstract: A semiconductor device including a reduced surface field strength type LDMOS transistor which can prevent the breakdown of elements at channel formation portions when a reverse voltage is applied to its drain. A P well and an N well are formed in an N-type substrate to produce a double-well structure, with a source electrode being set to be equal in electric potential to the N-type substrate. The drift region of the N well has a dopant concentration to satisfy the so-called RESURF condition, which can provide a high breakdown voltage a low ON resistance. When a reverse voltage is applied to a drain electrode, a parasitic bipolar transistor comprising the N well, the P well and the N-type substrate develops to form a current-carrying path toward a substrate, so that the element breakdown at the channel formation portions is avoidable at the application of the reverse voltage.

Abstract: A method for fabricating a semiconductor power integrated circuit includes the steps of forming a semiconductor structure having at least one active region, wherein an active region includes a well region for forming a source and a drift region for forming a drain region, forming a trench for isolation of the active regions, wherein the trench has a predetermined depth from a surface of the semiconductor structure, forming a first TEOS-oxide layer inside the trench and above the semiconductor structure, wherein the first TEOS-oxide layer has a predetermined thickness from the surface of the semiconductor device, forming a second TEOS-oxide layer on the first TEOS-oxide layer, wherein a thickness of the second TEOS-oxide layer is smaller than that of the first TEOS-oxide layer, and performing a selective etching to the first and second TEOS-oxide layers, to thereby simultaneously form a field oxide layer pattern, a diode insulating layer pattern and a gate oxide layer pattern, to thereby reduce processing step

Abstract: A lateral IGBT comprises an N−-type island region, a P-type base layer and P-type drain layer formed in the N−-type island region, an N+-type source layer formed in the P-type base layer, a source electrode connected to the P-type base layer and N+-type source layer, a drain electrode connected to the P-type drain layer, a gate oxide film and field oxide film formed on the N−-type island region, and a gate electrode formed on the gate oxide film. In this invention, an electrically floating P-type diffusion layer is formed in the N−-type island region below the end region of the gate electrode.

Abstract: According to the present invention, there is provided an N-type insulated gate field effect transistor using an SOI substrate of which Si layer as a device formation area is N-type. The SOI substrate provided as the device formation area has the N-type semiconductor region, which has an impurity concentration higher than the impurity concentration of the device formation area, formed so that the N-type semiconductor region is contacted to a part of a gate insulating film and a field silicon oxide film formed between a source electrode and a drain electrode, and extends to be contacted to the N-type semiconductor diffusion layer contacted to the drain electrode. According to the above arrangement, the on-state breakdown can be remarkably improved.

Abstract: In important applications of circuits comprising transistors of the lateral DMOST type, such as (half) bridges, the voltage on the output may become higher or lower than the supply voltage or earth in the case of an inductive load. The injection of charge carriers into the substrate can be prevented by screening the drain (18) of the Low-Side transistor from the substrate by means of a p-type buried layer (13) and an n-type buried layer (14) below said p-type buried layer. In order to avoid parasitic npn-action between the n-type buried layer (14) and the n-type drain (18), not only the back-gate regions (16a, 16c) at the edge of the transistor, but also the back-gate regions (16b) in the center of the transistor, are connected to the p-type buried layer, for example by means of a p-type well. As a result, throughout the relatively high-ohmic buried layer, the potential is well defined, so that said npn-action is prevented.

Abstract: An integrated circuit (10) includes a P-epi substrate (12) having therein an n-well isolation layer (13) and a p-well (14) within the n-well. The p-well includes adjacent an upper surface thereof a p+ layer (18) having several elongate parallel openings (21-23) therethrough. Each of the openings has therein a respective n− RESURF layer (26-28). Each n− RESURF layer has therethrough a respective further elongate opening (31-33), and has a uniform horizontal thickness all around that opening. Each of the openings in the RESURF layers has therein an n+ finger (36-38). The p+ layer and the n+ fingers each have a vertical thickness which is greater than the vertical thickness of the n− RESURF layers. The p+ layer serves as the anode of a zener diode, and the n+ fingers are interconnected and serve as the cathode.

Abstract: A MOS type semiconductor apparatus is provided that includes a first MOS type semiconductor device through which main current flows, and a second MOS type semiconductor device through which current that is smaller than the main current flows. The first and second MOS type semiconductor devices provided on the same semiconductor substrate have substantially the same structure, and have a common drain electrode. A gate electrode of the second MOS type semiconductor device is connected to the common drain electrode. The semiconductor apparatus further includes a plurality of pairs of Zener diodes which are connected in series and provided between the source electrode of the second MOS type semiconductor device and the gate electrode of the first MOS type semiconductor device. Each pair of Zener diodes are reversely connected to each other.

Abstract: An ESD protection circuit comprising a substrate having a first conductivity type, a well region having a second conductivity type, a first doping region having the first conductivity type, and a second doping region having the second conductivity type. The substrate is coupled to the reference potential, the well region is formed on the substrate and electrically coupled to the node, the first doping region is electrically floated on the surface of the well region, and the second doping region is disposed on the substrate and electrically coupled to the reference potential. Moreover, the electrostatic discharge current of the node provides a voltage with sufficient magnitude to breakdown the conjunction interface between the well region and the substrate, also triggering a BJT comprising the well region, substrate and the second doping region for dissipating the electrostatic discharge current.

Abstract: A semiconductor device including a reduced surface field strength type LDMOS transistor which can prevent the breakdown of elements at channel formation portions when a reverse voltage is applied to its drain. A P well and an N well are formed in an N-type substrate to produce a double-well structure, with a source electrode being set to be equal in electric potential to the N-type substrate. The drift region of the N well has a dopant concentration to satisfy the so-called RESURF condition, which can provide a high breakdown voltage a low ON resistance. When a reverse voltage is applied to a drain electrode, a parasitic bipolar transistor comprising the N well, the P well and the N-type substrate develops to form a current-carrying path toward a substrate, so that the element breakdown at the channel formation portions is avoidable at the application of the reverse voltage.

Abstract: A method and apparatus for increasing a breakdown voltage of a semiconductor device. The semiconductor device is constructed on a semiconductor substrate including an isolation diffusion region around the semiconductor device, a substrate layer, an epi layer on top of the substrate layer, a surface diffusion region extending into the epi layer from a top surface of the epi layer and a metallization line coupled to the surface diffusion, wherein the metallization line traverses the semiconductor device and the isolation diffusion region. The semiconductor device also includes a poly field plate over the isolation diffusion region and beneath the metallization line, a field limiting diffusion region provided in the epi layer between the surface diffusion region and the isolation diffusion region and below the metallization line, and a contact coupled to the field limiting diffusion region, wherein the contact extends to a region below the metallization line and overlapping the poly field plate.

Abstract: A semiconductor device (10) comprises a reduced surface field (RESURF) implant (14). A field oxide layer (20), having a length, is formed over the RESURF implant (14). A field plate (12) extends from a near-side of the field oxide layer (20) and over at least one-half of the length of the field oxide layer (20).

Abstract: The invention relates to a half-bridge circuit comprising two series-connected n-channel DMOS transistors, in which the source of the one transistor, the low-side transistor T.sub.1, is connected to a low-voltage terminal V.sub.ss, and the drain of the other transistor, the high-side transistor T.sub.2, is connected to a high-voltage terminal V.sub.dd. The drain of the low-side transistor and the source of the high-side transistor are connected to the output terminal (4). The circuit is arranged in a semiconductor body having an n-type or p-type epitaxial layer (11) which is applied to a p-type substrate (10). In the epitaxial layer, two n-type regions are defined for the transistors, each of said regions forming a drift region of one of the transistors and being surrounded by a cup-shaped n-type zone in the semiconductor body. Within the n-type cup-shaped zone (12) of the low-side transistor T.sub.1, there is provided a p-type cup-shaped zone which isolates the drift region (15) of T.sub.

Abstract: A transistor including a source region 506 in a semiconductor body 502; a bulk region 508 in the semiconductor body adjacent the source region; a drain region in the semiconductor body adjacent the bulk region but opposite the source region, the drain region including doped regions 504,514 of n and p dopant types; and a field plate 516 formed over the semiconductor body adjacent the drain region between the drain region and the bulk region.

Abstract: A semiconductor device including a reduced surface field strength type LDMOS transistor which can prevent the breakdown of elements at channel formation portions when a reverse voltage is applied to its drain. A P well and an N well are formed in an N-type substrate to produce a double-well structure, with a source electrode being set to be equal in electric potential to the N-type substrate. The drift region of the N well has a dopant concentration to satisfy the so-called RESURF condition, which can provide a high breakdown voltage a low ON resistance. When a reverse voltage is applied to a drain electrode, a parasitic bipolar transistor comprising the N well, the P well and the N-type substrate develops to form a current-carrying path toward a substrate, so that the element breakdown at the channel formation portions is avoidable at the application of the reverse voltage.

Abstract: A termination structure for semiconductor devices and a process for fabricating the termination structure are described and include a layer of amorphous silicon for passivating and terminating the device junctions. The layer of amorphous silicon is deposited atop the metal contact and atop and overlying insulation layer and expose the source pad. A layer of silicon nitride may be deposited atop the layer of amorphous silicon. The layer of amorphous silicon minimizes gate leakage.

Abstract: The high breakdown voltage semiconductor device comprises an insulating film, a semi-insulating high resistance film formed on the insulating film, a first semiconductor layer of the first conductivity type formed on the high resistance film, a second semiconductor layer of the second conductivity type formed on a surface of the first semiconductor layer, a third semiconductor layer of the first conductivity type formed on the surface of the first semiconductor layer so as to be apart from the second semiconductor layer, and having an impurity concentration higher than that of the first semiconductor layer, and a resurf layer formed in a space between the second and third semiconductor layers on the surface of the first semiconductor layer, and having an impurity concentration lower than that of the second semiconductor layer.

Abstract: Silicon carbide power devices include a semiconductor substrate of first conductivity type (e.g., N-type) having a face thereon and a blocking voltage supporting region of first conductivity type therein extending to the face. The voltage supporting region is designed to have a much lower majority carrier conductivity than an underlying and highly conductive "bypass" portion of the semiconductor substrate. This bypass portion of the substrate supports large lateral currents with low on-state voltage drop. First and second semiconductor devices are also provided having respective first and second active regions of first conductivity type therein. These first and second active regions extend on opposing sides of the voltage supporting region and are electrically coupled to the bypass portion of the semiconductor substrate which underlies and extends opposite the voltage supporting region relative to the face of the substrate.

Abstract: A high breakdown-voltage diode is provided, which has a decreased chip area and a low electric resistance between anode and cathode regions after the breakdown phenomenon takes place. A semiconductor layer of a first conductivity type is vertically isolated by a first isolation dielectric and laterally isolated by a second isolation dielectric from outside. A first diffusion region of a second conductivity type is formed in a surface area of the semiconductor layer, thereby forming a first p-n junction. A second diffusion region of the first conductivity type is formed in the surface area to be apart from the first diffusion region. A third diffusion region of the second conductivity type is formed in the surface area between the first and second diffusion regions, thereby forming a second p-n junction. The third diffusion region is electrically connected to the first diffusion region.

Abstract: A bidirectional lateral insulated gate bipolar transistor (IGBT) includes two gate electrodes. The IGBT can conduct current in two directions. The IGBT relies on a double RESURF structure to provide high voltage blocking in both directions. The IGBT is symmetrical, having an N-type drift region in contact with an oxide layer. A P-type region is provided above the N-type drift region, having a portion more heavily doped with P-type dopants. The double RESURF structure can be provided by a buried oxide layer, a floating doped region, or a horizontal PN junction. The IGBT can be utilized in various power operations, including a matrix switch or a voltage source converter.

Abstract: A semiconductor device includes a first semiconductor layer of a first conductivity type having first and second main surfaces, a second semiconductor layer of a second conductivity type selectively formed on the first main surface of the first semiconductor layer, the second semiconductor layer including a first region having a relatively high injection efficiency and a second region having a relatively low injection efficiency and the first region being surrounded by the second region, a third semiconductor layer of the first conductivity type formed on the second main surface of the first semiconductor layer, a first electrode selectively formed on the second semiconductor layer of the second conductivity type and connected to at least the first region, and a second electrode formed on the third semiconductor layer of the first conductivity type.

Abstract: A lateral field effect transistor improves the trade-off relationship between the breakdown voltage and on-resistance of a lateral MOSFET integrated into a power IC. A MOSFET is formed by forming a p-type well region on a p-type substrate, and an n-type drain region accompanying an n-type offset region on the well region. A thick oxide film is disposed on the offset region. The surface concentration of the offset region is, preferably, from 5.times.10.sup.16 to 2.times.10.sup.17 cm.sup.-3 and the diffusion depth thereof is from 0.5 to 1.5 .mu.m. The maximum impurity concentration of a p-type well region is preferably adjusted to be from 5.times.10.sup.15 to 3.times.10.sup.16 cm.sup.-3. By the shallow junction depth of the offset region that promotes depletion thereof, the breakdown voltage is increased. Also, by the high maximum impurity concentration of the well region of from 5.times.10.sup.15 to 3.times.10.sup.16 cm.sup.-3, the on-resistance is lowered.

Abstract: A resurf structure is provided which includes an n type diffusion region surrounded by a n- diffusion region, in which a part of the joined combination of the n type diffusion region and the n- diffusion region is separated by a narrow p- substrate region in between. An aluminum lead is provided between the separated n- diffusion regions, and a signal is level shifted. A high voltage semiconductor device which includes a small area high voltage isolation region is obtained without process cost increase.

Abstract: In many circuits in which a current is switched off, a high voltage appears at the drain electrode of a transistor, in particular in the case of an inductive load. When a lateral high-voltage DMOST is used, such a high voltage may lead to instability in the transistor characteristics or may even damage the transistor. To avoid this problem, the drain of a high-voltage LDMOST is locally provided with a strongly doped n-type zone 18, 21 (in the case of an n-channel transistor) which extends, seen from the surface, down into the semiconductor body to a greater depth than does the source zone 8, so that a pn-junction is formed at a comparatively great depth in the semiconductor body having a breakdown voltage that is lower than the BV.sub.ds of the transistor without this zone. The energy stored in the inductance may thus be drained off through breakdown of the pn-junction.

Abstract: A high breakdown voltage semiconductor device formed in an SOI structure is disclosed. An MOS transistor composed of a drift layer, p well, a source, a gate, and a drain is formed in an island region surrounded by insulators on a semiconductor substrate. Furthermore, an electricfield-alleviating layer is formed in a bottom portion of the Si island region. The electric-field-alleviating layer is a semiconductor layer of exceeding low concentration, e.g., intrinsic, and therefore a virtual PIN structure is structured among the p well and the drift layer. Because the electric-field-alleviating layer corresponds to an I layer of the PIN structure, a depletion layer is created within the electric-field-alleviating layer when high voltage is applied to the MOS transistor, the high voltage is distributed throughout this depletion layer, and high breakdown voltage can be obtained.

Abstract: The epitaxial substrate of a semiconductor chip device has a resurf diffusion in at least one of its isolated wells in the device chip surface. The wells are separated by junction diffusions. The thickness of the epitaxial layer is reduced by placing an increased percentage of its total charge for given a breakdown voltage (punch-through voltage) in the lower portion of the layer.

Abstract: N-channel LDMOS and p-channel MOS devices for high voltage integrated in a BiCMOS integrated circuit and exploiting a RESURF condition are provided with a buried region of the same type of conductivity of the epitaxial layer and a doping level intermediate between the doping level of the epitaxial layer and the doping level of a well region. The devices may be configured as source or drain followers without problems.

Abstract: A power transistor incorporating a constant-voltage diode maintains the breakdown voltage of the constant-voltage diode at a specified level and prevents local breakdown of an insulating film located between an A1 field plate electrode and a base region of the transistor by spacing the A1 field plate electrode located on a collector region by a distance "d" from the base region.

Abstract: An integrated device including a structure for protection against electric fields. The protection structure may include a first region of conducting material electrically connected to the gate/source region of the device at a first potential. The protection structure may also include a second region of conducting material electrically connected to the drain region of the device at a second potential differing from the first. In one embodiment, the first region of conducting material is comb-shaped, and includes a first number of fingers separated by a plurality of gaps. The second region of conducting material includes portions extending at the aforementioned gaps to form a comb structure. Thus, the body of semiconductor material of the device sees a protection region formed by a pair of interlocking comb structures at an intermediate potential between the first and second potentials.

Abstract: A back-source MOSFET uses a source electrode on a second surface of a substrate to reduce noise which would otherwise interfere with the logic circuit of a power integrated circuit. One embodiment includes a substrate of a first conductivity type and a base layer of a second conductivity type on a first surface of the substrate. A source region is electrically connected with the substrate. A source electrode is formed on a second surface of the substrate. A further embodiment includes a substrate of a first conductivity type and a base layer of a first conductivity type on a first surface of the substrate. A source electrode is formed on a second surface of the substrate.

Abstract: In a semiconductor electron emission device for causing an avalanche breakdown by applying a reverse bias voltage to a Schottky barrier junction between a metallic material or metallic compound material and a p-type semiconductor, and externally emitting electrons from a solid-state surface, a p-type semiconductor region (first region) for causing the avalanche breakdown contacts a p-type semiconductor region (second region) for supplying carriers to the first region, and a semi-insulating region is formed around the first region.

Abstract: An n- or p-doped semiconductor region accommodates the depletion zone of an active area of the semiconductor component with a vertical extension dependent upon an applied blocking voltage. The junction termination for the active area is constituted with a semiconductor doped oppositely to the semiconductor region, and is arranged immediately adjacently around the active area on or in a surface of the semiconductor region. The lateral extension of the junction termination is greater than the maximum vertical extension of the depletion zone, and the semiconductor region as well as the junction termination are constituted with a semiconductor with a band gap of at least 2 eV.

Abstract: A high voltage transistor includes a semiconductor-on-insulator (SOI) region in which a source and a channel are formed. A drain drift region is further formed partly in the SOI region and partly in the bulk silicon region beyond SOI and a gate is coupled to said SOI channel.

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 semiconductor device of the RESURF type with a "low-side" lateral DMOST (LDMOST), comprising a semiconductor body (1) of predominantly a first conductivity type and a surface region (3) adjoining a surface (2) and of a second conductivity type. 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 present at a distance from the back gate region (5). A separation region (15) of the first conductivity type is provided around the LDMOST in the surface region (3), which separation region adjoins the surface (2) and extends towards the semiconductor body (1).

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 lateral silicon carbide transistor (10) utilizes a modulated channel region (18) to form an accumulation region that facilitates a low on-resistance. A doped region of the channel layer forms a channel insert (14) that also lowers the on-resistance of the transistor (10). A damage termination layer (27) is utilized to facilitate providing a high breakdown voltage. Field plates (23,24) also assists in increasing the breakdown voltage and decreasing the on-resistance of the transistor (10).

Abstract: In a semiconductor device including a composite substrate formed by bonding first and second semiconductor substrates to each other through an oxide film and an insulator isolation trench formed from a major surface of the first semiconductor substrate to reach the oxide film and to surround an element forming region, when the potential of the second substrate is set at a potential higher than the minimum potential in the element forming region of the first substrate, an breakdown voltage can be increased. In a semiconductor integrated circuit having an element isolation region, a semiconductor device of a perfect dielectric isolation structure having an element forming region having a thickness smaller than that of the element forming region of a P-N junction isolation structure is used to reduce, e.g., a base curvature influence, thereby obtaining a further high breakdown voltage.

Abstract: A high-breakdown-voltage MOS transistor includes a substrate of one conductivity and a semiconductor layer of the other conductivity type, a drain electrode, a diffusion layer of one conductivity type, a base region of one conductivity type, a source region, a gate electrode, a source electrode, and a heavily doped layer. The diffusion layer and the substrate are electrically connected to the source region.

Abstract: A lateral DMOS transistor structure formed in N-type silicon is disclosed which incorporates a special N-type enhanced drift region. In one embodiment, a cellular transistor with a polysilicon gate mesh is formed over an N epitaxial layer with P body regions, P.sup.+ body contact regions, N.sup.+ source and drain regions, and N enhanced drift regions. The N enhanced drift regions are more highly doped than the epitaxial layer and extend between the drain regions and the gate. Metal strips are used to contact the rows of source and drain regions. The N enhanced drift regions serve to significantly reduce on-resistance without significantly reducing breakdown voltage.

Abstract: A power semiconductor device having a source region (24) and a drain region (26) disposed in a semiconductor substrate (10). A composite drift region is formed of an n-type first drift region (12) in the substrate (10) and of a second drift region (36) composed of a second type of semiconductor material such as gallium arsenide or silican carbide which is a different material than that of the substrate.

Abstract: A high-breakdown voltage semiconductor device and a fabrication method are disclosed. A dielectric layer dielectrically isolates a semiconductor substrate from an n.sup.- type semiconductor layer. An n.sup.+ type semiconductor region having a lower resistance than the n.sup.+ type semiconductor layer is formed as if surrounded by a p.sup.+ type semiconductor region. The dielectric layer consists of a relatively thick first region and a relatively thin second region. The n.sup.+ type semiconductor region, which is located above the first region, occupies a narrower area than the first region. Thus, by forming the dielectric layer thick immediately under the first semiconductor layer and controlling the thickness of the dielectric layer at other potions, the breakdown voltage of the semiconductor device is improved without curbing RESURF effect.

Abstract: A high voltage diode having a field plate and substrate separated from a high impurity concentration region by dielectric layers and biased to deplete the high impurity concentration region therebetween before critical field for avalanche is reached for the region.

Abstract: A semiconductor device is supported by a semiconductor body which comprises a substrate, an oxide layer and a weakly doped monocrystalline wafer. Trenches for a dielectrically isolating layer which surrounds a component region are etched in the wafer. A field effect transistor in the component region has two doped wafer-line gate regions, which have been diffused in the component region with the aid of a first mask. Two heavily doped regions are diffused in the component region with the aid of a second mask, these regions forming the source region and the drain region of the transistor. The semiconductor body is easy to produce and is available commercially, which simplifies manufacture of the field effect transistor. Manufacture is also simplified because the configuration of both the component region and the parts of the transistor are determined by the simple choice of masks. The component region is weakly doped and is easy to deplete of charge carriers.

Abstract: A transistor (10) has a thin epitaxial layer (14) of a second conductivity type on a semiconductor substrate (12) of a first conductivity type. A drift region (24) of the second conductivity type is formed extending through the thin epitaxial layer (14) to the substrate (12). A thick insulator layer (26) is formed on the drift region (24). An IGFET body (28) of the first conductivity type is formed adjacent the drift region (24). A source region (34) of the second conductivity type is formed within the IGFET body (28) and spaced from the drift region (24) defining a channel region (40) within the IGFET body (28). A conductive gate (32) is insulatively disposed over the IGFET body (28) and extends from the source region (34) to the thick insulator layer (26). A drain region (36) is formed adjacent the drift region (24).

Abstract: A lateral Semiconductor-On-Insulator (SOI) device includes a substrate, a buried insulating layer on the substrate, and a lateral semiconductor device such as an LDMOS transistor, an LIGBT or a lateral thyristor on the insulating layer. The semiconductor device (in the case of an LDMOS transistor) includes a source region, a channel region, an insulated gate electrode over the channel region, a lateral drift region formed of a continuous layer of a lightly-doped semiconductor material on the buried insulating layer, and a drain contact region which is laterally spaced apart from the channel region and connected to the channel region by the drift region. A buried diode is formed in the substrate, and is electrically coupled to the drain contact region by a portion of the drift region which extends laterally in the region between the drain contact region and the buried diode.