Abstract: Memory cells are constructed from double-gated four terminal transistors having independent gate control. DRAM cells may use one, two or three transistors. Single transistor cells are constructed either with or without a bit storage capacitor, and both NAND- and NOR-type Non-Volatile NVRAM cells, as well as Ferroelectric FeRAM cells, are described. For all cells, top gates provide conventional access while independent bottom gates provide control to optimize memory retention for given speed and power parameters as well as to accommodate hardening against radiation. In a single transistor cell without a capacitor, use of the bottom gate allows packing to a density approaching 2 F2. Using a ferroelectric material as the gate insulator produces a single-transistor FeRAM cell that overcomes the industry-wide Write Disturb problem. The memory cells are compatible with SOI logic circuitry for use as embedded RAM in SOC applications.

Abstract: A semiconductor device, such as a LDMOS device, comprising: a semiconductor substrate; a drain region in the semiconductor substrate; a source region in the semiconductor substrate laterally spaced from the drain region; and a drift region in the semiconductor substrate between the drain region and the source region. A gate is operatively coupled to the source region and is located offset from the drain region on a side of the source region opposite from the drain region. When the device is in an on state, current tends to flow deeper into the drift region to the offset gate, rather than near the device surface. The drift region preferably includes at least first and second stacked JFETs.

Abstract: An industrial control circuit includes: a first isolation circuit (22) for converting an analog signal to a low level voltage; a single-chip microprocessor SCM (23) for receiving the low level voltage from the first isolation circuit, and generating a control signal according to the low level voltage; and a second isolation circuit (24) for converting the control signal to a high level voltage. The SCM has at least thirty-two input/output (I/O) channels. Because the SCM used in the industrial control circuit has at least thirty-two I/O channels, the industrial control circuit can synchronously deal with sixteen-bit bidirectional communication.

Abstract: Disclosed is a silicon-on-insulator-based Schottky barrier diode with a low forward voltage that can be manufactured according to standard SOI process flow. An active silicon island is formed using an SOI wafer. One area of the island is heavily-doped with an n-type or p-type dopant, one area is lightly-doped with the same dopant, and an isolation structure is formed on the top surface above a junction between the two areas. A metal silicide region contacts the lightly-doped side of the island forming a Schottky barrier. Another discrete metal silicide region contacts the heavily-doped area of the island forming an electrode to the Schottky barrier (i.e., a Schottky barrier contact). The two metal silicide regions are isolated from each other by the isolation structure. Contacts to each of the discrete metal silicide regions allow a forward and/or a reverse bias to be applied to the Schottky barrier.

Abstract: A Schottky barrier rectifier, in accordance with embodiments of the present invention, includes a first conductive layer and a semiconductor. The semiconductor includes a first doped region, a second doped region and a plurality of third doped regions. The second doped region is disposed between the first doped region and the first conductive layer. The plurality of third doped regions are disposed in the second doped region. The first doped region of the semiconductor is heavily doped with a first type of dopant (e.g., phosphorous or arsenic). The second doped region is moderately doped with the first type of dopant. The plurality of third doped regions are moderately to heavily doped with a second type of dopant.

Abstract: The self-aligned Schottky-barrier clamped planar DMOS transistor structure comprises a self-aligned source region being surrounded by a planar gate region. The self-aligned source region comprises a moderately-doped p-base diffusion ring being formed in a lightly-doped N? epitaxial semiconductor layer, a heavily-doped n+ source diffusion ring being formed within the moderately-doped p-base diffusion ring, and a Schottky-barrier contact with the moderately-doped p-base diffusion ring acted as a diffusion guard ring being formed in a middle semiconductor surface portion of the self-aligned source region. The planar gate region comprises a patterned heavily-doped polycrystalline-silicon gate layer being silicided with or without metal silicide layers. The self-aligned source region further comprises a lightly-doped p? diffusion region being formed beneath a middle portion of the moderately-doped p-base diffusion ring.

Abstract: A SiC Schottky barrier diode (SBD) is provided having a substrate and two or more epitaxial layers, including at least a thin, lightly doped N-type top epitaxial layer, and an N-type epitaxial layer on which the topmost epitaxial layer is disposed. Multiple epitaxial layers support the blocking voltage of the diode, and each of the multiple epitaxial layers supports a substantial portion of the blocking voltage. Optimization of the thickness and dopant concentrations of at least the top two epitaxial layers results in reduced capacitance and switching losses, while keeping effects on forward voltage and on-resistance low. Alternatively, the SBD includes a continuously graded N-type doped region whose doping varies from a lighter dopant concentration at the top of the region to a heavier dopant concentration at the bottom.

Abstract: A method of forming memory circuitry having a memory array having a plurality of memory capacitors and having peripheral memory circuitry operatively configured to write to and read from the memory array, includes forming a dielectric well forming layer over a semiconductor substrate. A portion of the well forming layer is removed effective to form at least one well within the well forming layer. An array of memory cell capacitors is formed within the well. The peripheral memory circuitry is formed laterally outward of the well forming layer memory array well. In one implementation, memory circuitry includes a semiconductor substrate. A plurality of word lines is received over the semiconductor substrate. An insulative layer is received over the word lines and the substrate. The insulative layer has at least one well formed therein. The well has a base received over the word lines. The well peripherally defines an outline of a memory array area.

Abstract: Schottky barrier diodes use a dielectric separation region to bound an active region. The dielectric separation region permits the elimination of a guard ring in at least one dimension. Further, using a dielectric separation region in an active portion of the integrated circuit device may reduce or eliminate parasitic capacitance by eliminating this guard ring.

Abstract: Multi-terminal electronic switching devices comprising a chalcogenide material switchable between a resistive state and a conductive state. The devices include a first terminal, a second terminal and a control terminal. Application of a control signal to the control terminal modulates the conductivity of the chalcogenide material between the first and second terminals and/or the threshold voltage required to switch the chalcogenide material between the first and second terminals from a resistive state to a conductive state. The devices may be used as interconnection devices or signal providing devices in circuits and networks.

Abstract: A process for fabricating a dual charge storage location, electrically programmable memory cell, comprising: forming a first dielectric layer over a semiconductor material layer of a first conductivity type; forming a charge trapping material layer over the first dielectric layer; selectively removing the charge trapping material layer from over a central channel region of the semiconductor material layer, thereby leaving two charge trapping material layer portions at sides of the central channel region; masking the central channel region and selectively implanting dopants of a second conductivity type into the semiconductor material layer to form memory cell source/drain regions at sides of the two charge trapping material layer portions; forming a second dielectric layer over the charge trapping material layer; and forming a polysilicon gate over the second dielectric layer, the polysilicon gate being superimposed over the central channel region and the two charge trapping material layer portions.

Abstract: Silicon carbide metal-oxide semiconductor field effect transistors (MOSFETs) and methods of fabricating silicon carbide MOSFETs are provided. The silicon carbide MOSFETs have an n-type silicon carbide drift layer, spaced apart p-type silicon carbide regions in the n-type silicon carbide drift layer and having n-type silicon carbide regions therein, and a nitrided oxide layer. The MOSFETs also have n-type shorting channels extending from respective ones of the n-type silicon carbide regions through the p-type silicon carbide regions to the n-type silicon carbide drift layer. In further embodiments, silicon carbide MOSFETs and methods of fabricating silicon carbide MOSFETs are provided that include a region that is configured to self-deplete the source region, between the n-type silicon carbide regions and the drift layer, adjacent the oxide layer, upon application of a zero gate bias.

Abstract: A process and related product in which ohmic contacts are formed in High Electron Mobility Transistors (HEMTs) employing compound substrates such as gallium nitride. An improved device and an improvement to a process for fabrication of ohmic contacts to GaN/AlGaN HEMTs using a novel two step resist process to fabricate the ohmic contacts are described. This novel two-step process consists of depositing a plurality of layers having compounds of Group III V elements on a substrate; patterning and depositing a first photoresist on one of the layers; etching recessed areas into this layer; depositing ohmic metals on the recessed areas; removing the first photoresist; patterning and depositing a second photoresist, smaller in profile than the first photoresist, on the layer; depositing more ohmic metal on the layer allowing for complete coverage of the recessed areas; removing the second photoresist, and annealing the semiconductor structure.

Abstract: A floating gate with multiple tips and a fabrication method thereof. A semiconductor substrate is provided, on which a patterned hard mask layer is formed, wherein the patterned hard mask layer has an opening. A gate dielectric layer and a first conducting layer with a first predetermined thickness are formed on the bottom of the opening. A spacer is formed on the sidewall of the opening. A conducting spacer is formed on the sidewall of the spacer. The first conducting layer is etched to a second predetermined thickness. A multi-tip floating gate is provided by the first conducting layer and the conducting spacer. A protecting layer is formed in the opening. The patterned hard mask layer, the gate dielectric layer, a portion of the protecting layer, and a portion of the first spacer are etched to expose the surface of the first conducting layer.

Abstract: A standard cell architecture with a basic cell that spans multiple rows of the standard cell. This multi-row basic cell may be a dual-height cell that spans two rows, or it may span more than two rows. The multi-row basic cell may be intermixed in a standard cell design with smaller, single-height cells for high-density applications. The single-height cells may be used where possible and higher-drive dual-height basic cells where larger transistors are desired. Other multiple height cells may also be included if even more current is desirable. The power rail may include conductors of varying width.

Abstract: In a semiconductor heterojunction corresponding to the n-channel and p-channel, the present invention is to enable the selective carrier injection into each channel by employing a height difference of a Schottky barrier, &phgr; B, which is provided between a source/drain consisting of metal or semiconductor-intermetallic compound and a semiconductor film used for each channel of the semiconductor.

Abstract: The invention provides an electrical contact device, a pre-assembly for producing the electrical contact device, and a method of forming the electrical contact device. The electrical contact device includes a plurality of fine pitch electrical leads disposed in parallel spaced apart relation. An insulating member encapsulates portions of the electrical leads which extend from opposite sides of the insulating member. The insulating member retains the electrical leads in position and electrically isolated from one another. The contact device is used to facilitate connection with the leads of an IC package.

Abstract: This invention relates to a MOS transistor made in the thin film of silicon of an SOI chip (10), said thin film (13) being slightly doped and of less than 30 nm in thickness, the source (14) and drain (15) contacts being of the Schottky type at the lowest level of Schottky barrier possible for majority carriers, with an accumulation type transistor operation.

Abstract: A method for efficiently manufacturing a semiconductor device, the semiconductor device having an FET and a pn junction diode provided on the same semiconductor substrate, the FET having a Schottky junction for a gate electrode and a gate recess, includes the steps of forming a channel layer, a first etching stopper layer, an n-type common layer, a second etching stopper layer, a p-type layer, and a third etching stopper layer on the semiconductor substrate in that order; etching away the p-type layer and the third etching stopper layer in specific regions; simultaneously forming a source electrode, a drain electrode, a cathode; forming a mask having an opening for forming a gate recess and a gate electrode and an opening for forming an anode; forming the gate recess by etching while the third etching stopper layer prevents the p-type layer from being etched; and simultaneously forming the gate electrode and the anode.

Abstract: A phase change memory may be made using an isolation diode in the form of a Shottky diode between a memory cell and a word line. To reduce the leakage currents associated with the Shottky diode, a guard ring may be utilized.

Abstract: A method for fabricating a body contact silicon-on-insulator transistor (10) includes forming a semiconductor substrate (12) over an insulator (14) and lightly doping the semiconductor substrate (12) to form a body region (18). The method also includes forming a gate (20) over the semiconductor substrate (12) and separated from the semiconductor substrate (12) by a gate insulator layer (21). The gate (20) defines a source region (22), a drain region (24) and a contact region (26). The method also includes masking a portion (36) of the gate (20) and the contact region (26) and heavily doping the source region (22), the drain region (24) and an unmasked portion (36) of the gate (20) with a material having a conductivity substantially opposite a conductivity of the body region (18).

Abstract: A semiconductor thin film having extremely superior crystallinity and a semiconductor device using the semiconductor thin film having high performance are provided. The semiconductor thin film is manufactured in such a manner that after an amorphous semiconductor thin film is crystallized by using a catalytic element, a heat treatment is carried out in an atmosphere containing a halogen element to remove the catalytic element. The thus obtained crystalline semiconductor thin film has substantially {110} orientation. The concentration of C, N, and S remaining in the final semiconductor thin film is less than 5×1018 atoms/cm3, and the concentration of O is less than 1.5×1019 atoms/cm3.

Abstract: A vertical JFET architecture. Generally, an integrated circuit structure includes a semiconductor area with a major surface formed along a plane and a first source/drain doped region formed in the surface. A second doped region forming a channel of different conductivity type than the first region is disposed over the first region. A third doped region is formed over the second doped region having an opposite conductivity type with respect to the second doped region, and forming a source/drain region. A gate is formed over the channel to form a vertical JFET.

Abstract: A method of forming a cell memory structure including the step of planarizing an HDP/LDP oxide layer lying over a capacitor area. The method provides for the planarization of the cell storage node, good isolation between the transistor and storage node, reduced step height for the cell-transistor and has the potential for increasing the node capacitance (like DRAM storage node).

Abstract: The conventional compound semiconductor switching device is prone to have a large chip size as the gate width needs to be large for achieving a low insertion loss and the separation between the connecting pad and the circuit wiring needs to be larger than 20 &mgr;m for obtaining a proper isolation between them. The overall chip size is reduced, first, by reducing the gate width of the switching FET operating at frequencies above 2.4 GHz to 700 &mgr;m or smaller together with the omission of the shunt FET, and, then, by reducing the separation between the connecting pad and the circuit wiring to 20 &mgr;m or smaller. This reduction of the separation is made possible by the introduction of an insulating film and a impurity region between the outermost portion of the connecting pad and the substrate for preventing the extension of the depletion layer.

Abstract: A power MOS transistor that permits a large current to flow without a broad gate width being employed. The power MOS transistor includes a substrate of a first conductivity type; a well region of a second conductivity type; a first electrode region whose impurity concentration is higher than the well region; a region of a first conductivity type; and a second electrode region. The first electrode region, first-conductivity-type region and second electrode region are respectively arranged in this order spaced apart from one another in a first direction. The first-conductivity-type region includes a plurality of first-conductivity-type sub-regions, which are provided spaced apart from one another in a second direction that is orthogonal to the first direction. A surface channel region is formed between adjacent first-conductivity-type sub-regions.

Abstract: Openings are formed in a laminate of a polycrystalline silicon film and an LTO film on a channel layer. While the laminate is used as a mask, impurities are implanted into a place in the channel layer which is assigned to a source region. Also, impurities are implanted into another place in the channel layer which is assigned to a portion of a second gate region. A portion of the polycrystalline silicon film which extends from the related opening is thermally oxidated. The LTO film and the oxidated portion of the polycrystalline silicon film are removed. While a remaining portion of the polycrystalline silicon film is used as a mask, impurities are implanted into a place in the channel layer which is assigned to the second gate region. Accordingly, the source region and the second gate region are formed on a self-alignment basis which suppresses a variation in channel length.

Abstract: In a semiconductor storage device, a line of lower-side backing wiring is provided on a line of gate wiring via an insulation layer, and a line of upper-side backing wiring is provided further on the top layer thereof via another insulation layer. Contacts between the gate wiring and upper-side backing wiring are distributed and arranged on two or more different lines extending in a vertical direction with respect to a direction to which the gate wiring extends, and any contacts adjacent to each other of the contacts are arranged on different lines. The lower-side backing wiring passes through between the adjacent contacts.

Abstract: A semiconductor memory cell comprising a first transistor for readout, a second transistor for switching, and having a first region, a second region formed in a surface region of the first region, a third region formed in a surface region of the second region, a fourth region formed in a surface region of the first region and spaced from the second region, a fifth region formed in a surface region of the fourth region, and a gate region, wherein when the semiconductor memory cell is cut with a first imaginary perpendicular plane which is perpendicular to the extending direction of the gate region and passes through the center of the gate region, the second region and the fourth region in the vicinity of the gate region are nearly symmetrical with respect to a second imaginary perpendicular plane which is in parallel with the extending direction of the gate region and passes through the center of the gate region.

Abstract: An FAMOS memory includes memory cells, with each memory cell including an insulated gate transistor, and a first access transistor having a drain connected to a source of the insulated gate transistor. The FAMOS memory also includes an insulation transistor having a drain and a source respectively connected to the source of the insulated gate transistors of two adjacent cells of a same row. Each insulated gate transistor has a ring structure, and a ladder-shaped separation region insulates the cells of the same row.

Abstract: The present invention relates to an improved memory circuit with a divided bit-line, shared sense amplifier architecture. In a conventional divided bit-line, shared sense amplifier configuration, two adjacent memory sub-arrays are generally located between two banks of sense amplifiers and selected bit lines of the two adjacent memory sub-arrays are generally connected to metal lines with metal contacts to reduce capacitive loading. Under the present invention, some sense amplifiers from either banks of sense amplifiers are repositioned to the area between the two adjacent memory sub-arrays thereby permitting the repositioned sense amplifiers to be shared. As a result, any two adjacent memory sub-arrays share a bank of sense amplifiers. Furthermore, selected bit lines from the two adjacent memory sub-arrays are coupled to metal lines within the repositioned sense amplifiers.

Abstract: An integrated circuit, such as a DRAM circuit, having a plurality of cells is formed in containers formed an isolation layer positioned on an first surface of a semiconductor substrate. The containers have a first region located proximal the first surface of the semiconductor substrate that has a first cross-sectional area and a second region located distal from the first surface of the semiconductor substrate that has a second cross-sectional area that is less than the first cross-sectional area. Cells, such as capacitors, are formed in the containers and the isolation material positioned between adjacent cells is removed so that a generally horizontal surface is formed. The horizontal surface is located closer to the first surface of the substrate than the transition between the first region and the second region of the container so that substantially vertical surfaces are formed in the isolation region linking the cells to the horizontal surface of the isolation layer.

Abstract: A semiconductor rectifier includes a substrate of a first conductivity type; a current path layer of the first conductivity type formed near the surface of the substrate; a current block layer of a second conductivity type laterally enclosing the current path layer and extending to a depth deeper than the current path layer; and first and second metal layers formed respectively contacting upper and lower surfaces of the substrate. The current path layer has an impurity concentration higher than that of the substrate, and the current block layer has an impurity concentration higher than that of the current path layer. The current path layer is small enough for the portion below the current path layer to be completely blocked by the depletion region formed around the current block layer when a reverse bias or no is applied to the rectifier.

Abstract: An inventive semiconductor memory device includes a memory circuit and a logic circuit that are formed on a single semiconductor substrate. The memory circuit includes a storage element having a memory gate structure. The memory gate structure includes: a tunnel insulating film formed on the substrate; and a control gate electrode formed out of a gate prototype film. The logic circuit includes a logical element having a logic gate structure. The logic gate structure includes: a lower gate electrode formed out of the gate prototype film; and an upper gate electrode formed out of a conductor film on the lower gate electrode. The conductor film contains a metal. The memory gate structure includes no metal films.

Abstract: Self-aligned features of double sided integrated circuits are formed by modifying a buried layer in an integrated circuit substrate to provide a modified buried layer. The modified buried layer can be formed using ion implantation. In particular, a first feature on an upper surface of the integrated circuit is used as a mask during an ion implantation step. The first feature on the upper surface shields an underlying portion of the modified buried layer from the ion implantation, thereby preventing the modification of the underlying portion. The integrated circuit is flipped over and a lower surface of the integrated circuit is processed wherein a second feature is formed on the lower surface using the modified buried layer as a mask. Accordingly, the second feature is formed self-aligned to the modified buried layer and to the first feature.

Abstract: A semiconductor device has first and second opposed major surfaces (10a and 10b). A semiconductor first region (11) is provided between second (12 or 120) and third (14) regions such that the second region (12 or 120) forms a rectifying junction (13 or 130) with the first region (11) and separates the first region (11) from the first major surface (10a) while the third region (14) separates the first region (11) from the second major surface (10b). A plurality of semi-insulating or resistive paths (21) are dispersed within the first region (1′) such that each path extends through the first region from the second to the third region. In use of the device when a reverse biasing voltage is applied across the rectifying junction (13 or 130) an electrical potential distribution is generated along the resistive paths (21) which causes a depletion region in the first region (11) to extend through the first region (11) to the third region (14) to increase the reverse breakdown voltage of the device.

Abstract: A semiconductor configuration, in particular based on silicon carbide, is specified which rapidly limits a short-circuit current to an acceptable current value. For this purpose, when a predetermined saturation current is exceeded, a lateral channel region is pinched off, and the current is limited to a value below the saturation current.

Abstract: Devices with Schottky junctions are manufactured in that a semiconductor body with a substrate is provided with a first, for example n-type semiconductor region in the form of an epitaxial layer. A Schottky metal is locally provided thereon. A second semiconductor region is advantageously formed directly below the Schottky metal, with the purpose of adjusting the level of the Schottky barrier. Around this, a third semiconductor region is formed in the first region at at least two sides, which third region is then of the p-conductivity type and, when it entirely surrounds the second region, forms a so-called guard ring. A disadvantage of the above known method is that the devices obtained thereby have a (forward) current-voltage characteristic which is not very well controllable and reproducible. This hampers mass manufacture.

Abstract: In a semiconductor device including a MOSFET, a first semiconductor layer is formed over a silicon substrate and has a gate region. Further, a second semiconductor layer is formed over the first semiconductor layer with a gate oxide film therebetween, and has an active region. The active region has a source region, a drain region and a channel region. An insulator layer on the active region encloses a back gate wiring layer.

Abstract: A field control electrode 9 is formed over an insulating film 6 on a channel layer 2, between a gate electrode 5 and a drain electrode 8. Tantalum oxide (Ta.sub.2 O.sub.5), for example, may be used as the material for the insulating film 6.

Abstract: A semiconductor device which includes a channel region of predetermined conductivity type having a pair of opposing surfaces (11 or 33) , a control element of opposite conductivity type disposed on one of the opposing surfaces (13 or 31) and a pair of spaced apart electrodes (17, 19 or 35, 37) disposed over the other of the opposing surfaces. The control element and channel region form a pn junction therebetween. An electrically insulating layer (15) can be disposed between the spaced apart electrodes (17, 19) and the channel region (11) in a high frequency embodiment.

Abstract: A semiconductor device comprises a channel of a semiconductor material for passing carriers, a carrier injecting part for injecting the carriers into the channel and establishing an ohmic contact with the channel at a first location, a carrier collecting part for collecting the carriers from the channel, the carrier collecting part establishing an ohmic contact with the channel at a second, different location, a carrier control part provided on the channel at a third location located between the first and second locations, the carrier control part being applied with a control voltage and controlling the passage of the carriers through the channel from the carrier injecting means to the carrier collecting means in response to the control voltage, and an acceleration part provided between the first and third locations including the third location.

Abstract: The present invention is to provide a static induction semiconductor device with a distributed main electrode structure and a static induction semiconductor device with a static induction main electrode shorted structure where the main electrode region is composed of regions of higher and lower impurity densities relative to each other and formed partly in contact with the lower impurity density region as well, and alternatively a static induction short-circuit region opposite in conductivity type to the main electrode region is formed in the lower impurity density region surrounded by the higher impurity density region.

Abstract: A silicon carbide switching device includes a three-terminal interconnected silicon MOSFET and silicon carbide MESFET (or JFET) in a composite substrate of silicon and silicon carbide. For three terminal operation, the gate electrode of the silicon carbide MESFET is electrically shorted to the source region of the silicon MOSFET, and the source region of the silicon carbide MESFET is electrically connected to the drain of the silicon MOSFET in the composite substrate. Accordingly, three-terminal control is provided by the source and gate electrode of the silicon MOSFET and the drain of the silicon carbide MESFET (or JFET). The switching device is designed to be normally-off and therefore blocks positive drain biases when the MOSFET gate electrode is shorted to the source electrode. At low drain biases, blocking is provided by the MOSFET, which has a nonconductive silicon active region. Higher drain biases are supported by the formation of a depletion region in the silicon carbide MESFET (or JFET).

Abstract: A semiconductor device including a bipolar transistor, has a collector region including a first semiconductor region of the first conductivity type and a second semiconductor region of the first conductivity type having higher resistance than the first semiconductor region, a base region including a semiconductor region of the second conductivity type, and an emitter region including a semiconductor region of the first conductivity type. The semiconductor device further comprises a metal layer region for connecting the first semiconductor region and the collector electrode on the collector region provided within the second semiconductor region layer of the collector region.

Abstract: A high speed and highly functional MOSFET having a thin channel formed in a single crystalline layer is controlled by voltages applied to both an upper gate electrode and a buried gate layer that sandwich the channel therebetween.

Abstract: A semiconductor device wherein a bipolar transistor and a junction type field effect transistor which has a high voltage resisting property and a high mutual conductance are formed into a single chip to reduce the cost. A bipolar transistor formation region is separated from a junction type field effect transistor formation region by a transistor separating region. In the former region, a collector diffused layer is formed on the semiconductor substrate on which an epitaxial layer is formed, and a base diffused layer and a collector lead diffused layer are formed in the epitaxial layer with an element separating region interposed therebetween and connect to the collector diffused layer. Further, an emitter diffused layer is formed on the base diffused layer. In the latter region, a bottom gate diffused layer is formed on the semiconductor substrate, and a channel formation region is formed in the epitaxial layer and connects to the bottom gate diffused layer.

Abstract: A III-V compound planar HBT-FET device integrates field effect transistors (FETs) with heterojunction bipolar transistors (HBTs) formed on the same semiconductor substrate. An HBT fabricated on the substrate includes a collector, a base, and an emitter. The HBT emitter comprises a lightly doped layer of a first conductivity type deposited atop a heavily doped base layer of a second conductivity type, a lightly doped emitter cap layer of the first conductivity type deposited atop the emitter layer, and a heavily doped emitter contact layer of the first conductivity type deposited atop the emitter cap layer. A FET, isolated from the HBT by areas of ion implantation, is formed in the layers of material deposited during fabrication of the HBT. The FET has a source and a drain formed in the heavily doped emitter contact layer, a gate recess etched in the emitter contact layer between the source and drain, and a Schottky gate metal contact deposited on the lightly doped emitter cap layer exposed in the gate recess.

Abstract: A merged P-I-N/Schottky power rectifier includes trenches, and P-N junctions along the walls of the trenches and along the bottoms of the trenches. By forming the P-N junctions along the trench walls, the total area of the P-N junctions relative to the surface area of the device can be increased, to thereby improve the device's on-state characteristics without sacrificing the total area of the Schottky region. The trenches may be U or V shaped in transverse cross-section or of other transverse cross-sectional shape, and the trenches may be polygonal or circular in top view.

Abstract: A semiconductor device comprises: a drain region made of one conductivity type semiconductor substrate having first and second major surfaces; a source region made of one conductivity type first impurity region and formed inside said drain region with being in contact with said first major surface of the drain region; a gate electrode formed in a first groove having a U shape and covered with an insulating film, said U-shaped first groove being dug from said first major surface of the drain region into said inside of the drain region and positioned in contact with one side of said source region; a second groove dug from said first major surface into said inside of the drain region and positioned in contact with the other side of said source region, a metal functioning as a source electrode being embedded into said second groove so as to constitute a Schottky junction with said drain region; a drain electrode electrically connected to said second major surface of the drain region; and, a channel region formed