Abstract: A semiconductor device having an active region is formed in a layer provided on a semiconductor substrate. At least a portion of the semiconductor substrate below at least a portion of the active region is removed such that the portion of the active region is provided in a membrane defined by that portion of the layer below which the semiconductor substrate has been removed. A heat conducting and electrically insulating layer is applied to the bottom surface of the membrane. The heat conducting and electrically insulating layer has a thermal conductivity that is higher than the thermal conductivity of the membrane so that the heat conducting and electrically insulating layer allows heat to pass from the active region into the heat conducting and electrically insulating layer during normal operation of the device.

Abstract: A thermal oxidation process is used to fill trenches with an oxide; however, the oxidation process consumes some of the silicon. The embodiments herein advantageously apply this tendency for the oxidation process to consume silicon so as to convert all the silicon substrate material between the multiple trenches into an oxide. Therefore, because all of the silicon between the multiple trenches is consumed by the oxidation process, the multiple smaller trenches are combined into a single larger trench filled with the oxide.

Abstract: A floating-gate transistor for an integrated circuit is formed on a p-type substrate. An n-type region is disposed over the p-type substrate. A p-type region is disposed over the n-type region. Spaced apart n-type source and drain regions are disposed in the p-type region forming a channel therein. A floating gate is disposed above and insulated from the channel. A control gate is disposed above and insulated from the floating gate. An isolation trench disposed in the p-type region and surrounding the source and drain regions, the isolation trench extending down into the n-type region. The substrate, the n-type region and the p-type region each biased such that the p-type region is fully depleted.

Abstract: A non-volatile memory device includes a cell region having a memory gate pattern with a charge storage layer, and a peripheral region having a high-voltage-type gate pattern, a low-voltage-type gate pattern, and a resistor pattern. To fabricate the above memory device, a device isolation layer is formed in a substrate. Gate insulating layers having difference thickness are formed in low-and high-voltage regions of the peripheral region, respectively. A first conductive layer is formed over substantially the entire surface of a gate insulating layer in the peripheral region. A triple layer including a tunneling insulating layer, a charge storage layer, and a blocking insulating layer and a second conductive layer are sequentially formed over substantially the entire surface of the substrate including the first conductive layer.

Abstract: A super-lattice thermoelectric device. The device includes p-legs and n-legs, each leg having a large number of alternating layers of two materials with differing electron band gaps. The n-legs in the device are comprised of alternating layers of silicon and silicon germanium. The p-legs includes alternating layers of B4C and B9C. In preferred embodiments the layers are about 100 angstroms thick. Applicants have fabricated and tested a first Si/SiGe (n-leg) and B4C/B9C (p-leg) quantum well thermocouple. Each leg was only 11 microns thick on a 5 micron Si substrate. Nevertheless, in actual tests the thermocouple operated with an amazing efficiency of 14 percent with a Th of 250 degrees C. Thermoelectric modules made according to the present invention are useful for both cooling applications as well as electric power generation. This preferred embodiment is a thermoelectric 10×10 egg crate type module about 6 cm×6 cm×0.

Abstract: An RF circuit may be formed over a triple well that creates two reverse biased junctions. By adjusting the bias across the junctions, the capacitance across the junctions can be reduced, reducing the capacitive coupling from the RF circuits to the substrate, improving the self-resonance frequency of inductors and reducing the coupling of unwanted signals and noise from the underlying substrate to the active circuits and passive components such as the capacitors and inductors. As a result, radio frequency devices, such as radios, cellular telephones and transceivers such as Bluetooth transceivers, logic devices and Flash and SRAM memory devices may all be formed in the same integrated circuit die using CMOS fabrication is processes.

Abstract: A semiconductor memory device provides non-volatile memory with a memory array having an alternating Vss interconnection. Using the alternating Vss interconnection, a low implant dosage is added to a region proximate to the lower areas of an STI region, such as beneath the STI region, to ameliorate the problem of low Vss conductivity by providing an adequate number of multiple current paths over several Vss lines. However, non-adjacent STI regions, rather than adjacent STI region, receive the implant. Alternating Vss lines are interconnected by thus implanting under every other STI region. This alternating Vss interconnection imparts an adequately high Vss conductivity, yet without diffusion areas merging to isolate the associated memory device or contaminating the drains and maintains scalability.

Abstract: An integrated semiconductor circuit, having active components lying in mutually adjoining wells of a respective first and second conduction type, wherein the active components respectively are associated with substrate contacts lying in direct proximity to an edge bounding the mutually adjoining wells, is disclosed. Preferably, structures of the active components other than the contacts are arranged to lie further away from the edge and the circuit/layout structures are not mirror-symmetrical with respect to a center line of the circuit chip.

Abstract: An ESD-protection structure is located substantially under an integrated circuit bond pad. This ESD-protection structure is formed as a low capacitance structure by inserting a forward diode between the bond pad and the ESD clamp circuit. Placing the ESD-protection structure under the bond pad eliminates parasitic substrate capacitance and utilizes a parasitic PNP transistor formed from the inserted forward biased diode. The ESD-protection structure includes adjacent alternating P+ and N+ diffusions located substantially under a bond pad to be ESD protected. The P+ diffusions are connected to the bond pad metal with metal vias through an insulating layer. The N+ diffusions are adjacent to the P+ diffusions. An N+ diffusion surrounds the N+ and P+ diffusions, and ties together the N+ diffusions so as to form a continuous N+ diffusion completely around each of the P+ diffusions. An N? well is located substantially under the N+ and P+ diffusions.

Abstract: A semiconductor transistor structure includes a substrate having an epitaxial layer, a source region extending from the surface of the epitaxial layer, a drain region within the epitaxial layer, a channel located between the drain and source regions, and a gate arranged above the channel. The drain region includes a first region for establishing a contact with an electrode, a second region being less doped than the first region being buried within the epitaxial layer and extending from the first region horizontally in direction towards the gate, a third region less doped than the second region and extending vertically from the surface of the epitaxial layer and horizontally from the second region until under the gate, a top layer extending from the surface of the epitaxial layer to the second region, and a bottom layer extending from the second region into the epitaxial layer.

Abstract: A semiconductor device includes an N channel MOS transistor. The N channel MOS transistor includes a first P type buried layer that isolates an N epitaxial region on a P type substrate (P-SUB) from another N epitaxial region, a drain in an N well in the N epitaxial region, a source in a P well surrounding sides of the N well to isolate the N well, and a gate on upper layer portions of the drain and the source. The MOS transistor also includes a second P type buried layer between the N well and the P well and the substrate and contiguous to the P well, and an N buried layer contiguous to the P type buried layer and the P-SUB. The N epitaxial region, the P-SUB, and the first P type buried layer are connected to ground potential.

Abstract: A storage-type SiC-MISFET includes a SiC substrate, an n-type drift layer, a p-type well region, an n-type source region, a SiC channel layer which contains an n-type impurity and is to be a storage-type channel layer, a p-type heavily doped contact layer, a gate insulation film, a gate electrode and the like. In the storage-type SiC-MISFET, a partially heavily doped layer is formed by partially implanting ions of a p-type impurity into an upper surface portion of the n-type drift layer and containing an impurity of the same conductive type as that of the impurity implanted into the well region at a higher concentration than that in the well region.

Abstract: A plurality of devices, such as devices that are utilized for implementing radio frequency applications, can be formed in the same substrate. Each of these devices may be formed over a triple well that includes at least one well capable of being biased. Each of the wells is coupled to a well bias through a resistor. In some embodiments, a plurality of wells operating at a relatively high frequency may be connected to the same bias potential, each through separate resistors. The noise coupling may be reduced through the use of the bias resistors.

Abstract: A power semiconductor device has an active region that includes a drift region. At least a portion of the drift region is provided in a membrane which has opposed top and bottom surfaces. In one embodiment, the top surface of the membrane has electrical terminals connected directly or indirectly thereto to allow a voltage to be applied laterally across the drift region. In another embodiment, at least one electrical terminal is connected directly or indirectly to the top surface and at least one electrical terminal is connected directly or indirectly to the bottom surface to allow a voltage to be applied vertically across the drift region. In each of these embodiments, the bottom surface of the membrane does not have a semiconductor substrate positioned adjacent thereto.

Abstract: An ESD-protection device includes a gate electrode formed on a substrate; a first diffusion region of a first conductivity type formed in the substrate at a first side of the gate electrode, a second diffusion region of the first conductivity type formed in the substrate at a second side of the gate electrode, and a third diffusion region of a second conductivity type formed in the substrate underneath the second diffusion region in contact with the second diffusion region. Thereby, the impurity concentration level of the third diffusion region is set to be larger than the impurity concentration level of the region of the substrate located at the same depth right underneath the gate electrode.

Abstract: A semiconductor device comprises a semiconductor substrate, a first circuit formed on the substrate, and a second circuit connected to the first circuit as an input/output portion thereof and powered by a voltage higher than that for the first circuit, the first circuit including a first and a second field-effect transistor, the first drain region of the first transistor accompanying a first load capacitance, the second drain region of the second transistor accompanying a second load capacitance smaller than the first load capacitance, and the first gate insulation film of the first transistor having an average relative dielectric constant higher than that of the second gate insulation film of the second transistor, thereby realizing a high operation speed.

Abstract: A extractor implanted region is used in a silicon-on-insulator CMOS memory device. The extractor region is reversed biased to remove minority carriers from the body region of partially depleted memory cells. This causes the body region to be fully depleted without the adverse floating body effects.

Abstract: A p impurity region (3) defines a RESURF isolation region in an n− semiconductor layer (2). A trench isolation structure (8a) and the p impurity region (3) together define a trench isolation region in the n− semiconductor layer (2) in the RESURF isolation region. An nMOS transistor (103) is provided in the trench isolation region. A control circuit is provided in the RESURF isolation region excluding the trench isolation region. An n+ buried impurity region (4) is provided at the interface between the n− semiconductor layer (2) and a p− semiconductor substrate (1), and under an n+ impurity region 7 connected to a drain electrode (14) of the nMOS transistor (103).

Abstract: A conductive structure provides a conductive path from a first region in a semiconductor material to a second spaced apart region in the semiconductor material by forming a plurality of trenches between the first and second regions, implanting a dopant into the bottom surfaces of the trenches, and then annealing the wafer to cause the dopant at the bottom surfaces to diffuse and form a continuous conductive path.

Abstract: The present invention relates to a high-voltage semiconductor component having a semiconductor substrate of a first conduction type on which a semiconductor layer is provided as a drift path that takes up the reverse voltage of the semiconductor component. The semiconductor layer is either of the first conduction type or of a second conduction type that is opposite the first conduction type. The semiconductor layer is more weakly doped than the semiconductor substrate. Laterally oriented semiconductor regions of the first and second conduction types are alternately provided in the semiconductor layer. Furthermore, the present invention relates to a high-voltage semiconductor component having a MOS field-effect transistor that is formed in a semiconductor substrate and has a drift path that is connected to its drain electrode.

Abstract: In a gallium nitride semiconductor device comprising an active layer made of an n-type gallium nitride semiconductor that includes In and is doped with n-type impurity and a p-type cladding layer made of a p-type gallium nitride semiconductor that includes Al and is doped with p-type impurity,

Abstract: A power semiconductor device has an active region that includes a drift region. At least a portion of the drift region is provided in a membrane which has opposed top and bottom surfaces. In one embodiment, the top surface of the membrane has electrical terminals connected directly or indirectly thereto to allow a voltage to be applied laterally across the drift region. In another embodiment, at least one electrical terminal is connected directly or indirectly to the top surface and at least one electrical terminal is connected directly or indirectly to the bottom surface to allow a voltage to be applied vertically across the drift region. In each of these embodiments, the bottom surface of the membrane does not have a semiconductor substrate positioned adjacent thereto.

Abstract: A device comprising: a layer of gate oxide on a surface of the semiconductor substrate; a gate electrode formed on the surface of the gate oxide, the gate electrode having a drain side; a p-well implanted within a semiconductor substrate under the gate electrode; an n-well implanted in the p-well on the drain side; an n+ source region in the p-well outside of the n-well; an n+ drain region within the substrate inside the n-well; and lightly doped regions extending respectively from the source and drain regions toward the gate electrode.

Abstract: A power semiconductor device (10) has an active region that includes a drift region (20). At least a portion of the drift region (20) is provided in a membrane (16) which has opposed top and bottom surfaces (15,17). In one embodiment, the top surface (15) of the membrane (16) has electrical terminals connected directly or indirectly thereto to allow a voltage to be applied laterally across the drift region (20). In another embodiment, at least one electrical terminal is connected directly or indirectly to the top surface (15) and at least one electrical terminal is connected directly or indirectly to the bottom surface (17) to allow a voltage to be applied vertically across the drift region (20). In each of these embodiments, the bottom surface (17) of the membrane (16) does not have a semiconductor substrate positioned adjacent thereto.

Abstract: An object of the invention is to suppress degradation of the effective isolation width between a well and a diffusion layer caused by impurity ion implantation for forming the well performed at a predetermined incident angle. A well is formed by performing impurity ion implantation twice: first impurity ion implantation from a first direction at predetermined incident angle, acceleration voltage and dose; and second impurity ion implantation from a second direction different from the first direction by 180 degrees in a plan view at the same incident angle, acceleration voltage and dose as those in the first impurity ion implantation.

Abstract: A layer of material is transformed from a first state to a second state by the application of energy from an energy beam. For example, large direction- and location-controlled p-Si grain growth utilizes recrystallization of amorphous silicon from superpositioned laser irradiation. The superpositioned laser irradiation controls cooling and solidification processes that determine the resulting crystal structure. Specifically, a first laser beam of a first pulse duration is used to melt an amorphous silicon (a-Si) film and to create a temperature gradient. After an initial delay, a second laser beam with shorter pulse duration is superpositioned with the first laser beam. When a-Si is irradiated by the second laser beam, the area heated by the first laser beam becomes completely molten. Spontaneous nucleation is initiated in the supercooled liquid-Si when the liquid-Si temperature drops below the nucleation temperature.

Abstract: An object is to provide a semiconductor device which is free from such voltage oscillation as may cause malfunction of peripheral equipment. In a semiconductor device having a pin structure, the impurity concentration gradient in an n+ layer (103) serving as a buffer layer is set equal to or less than 2×1018cm−4. Then, when a reverse bias voltage is applied and a depletion layer reaches the n+ layer (103), the expansion of the depletion layer is prevented from rapidly stopping and the voltage oscillation can be suppressed.

Abstract: An integrated inductive element may be formed over a substrate. A triple well may be defined in a star-shape, in one embodiment, in the substrate beneath the integrated inductive element in order to reduce eddy current losses arising from magnetic coupling between integrated inductors associated with the same integrated circuit.

Abstract: An npn transistor allowing the potential of each terminal to be easily set and superior in characteristics such as withstand-voltage performance and current amplification factor can be obtained. An n-type buried layer on a p-type substrate, a p-type buried layer on the n-type buried layer, n-type epitaxial layers covering the above layers, terminal regions on the surfaces of the layers, p-type outer-periphery layers encircling the terminal regions, and an encirclement layer encircling the layers are included, and p-type base regions and the p-type outer-periphery layer are continued to the p-type buried layer to separate a collector region from a p-type substrate and the n-type buried layer and the n-type encirclement layer are continued to separate the p-type buried layer, the p-type base region, and the p-type outer-periphery layer from the p-type substrate.

Abstract: A compensation component includes a drift path formed of p-conducting and n-conducting layers which are led around or along a trench. A process for producing the compensation component is also provided.

Abstract: An RF circuit may be formed over a triple well that creates two reverse biased junctions. By adjusting the bias across the junctions, the capacitance across the junctions can be reduced, reducing the capacitive coupling from the RF circuits to the substrate, improving the self-resonance frequency of inductors and reducing the coupling of unwanted signals and noise from the underlying substrate to the active circuits and passive components such as the capacitors and inductors. As a result, radio frequency devices, such as radios, cellular telephones and transceivers such as Bluetooth transceivers, logic devices and Flash and SRAM memory devices may all be formed in the same integrated circuit die using CMOS fabrication processes.

Abstract: A semiconductor device has a drift region in which a drift current flows if it is in the ON mode and which is depleted if it is in the OFF mode. The drift region is formed as a structure having a plurality of first conductive type divided drift regions and a plurality of second conductive type compartment regions in which each of the compartment regions is positioned among the adjacent drift regions in parallel to make p-n junctions, respectively.

Abstract: A low junction capacitance semiconductor structure and an I/O buffer are disclosed. The semiconductor structure includes a MOS transistor and a lightly doped region. The MOS transistor is formed in a semiconductor substrate and has a gate and source and drain region formed aside the gate. The lightly doped region has a conductivity the same as the source and drain regions, and is formed in the drain region and has a depth larger than the source and drain regions. Further, the lightly doped region can be achieved by CMOS-compatible processes, and the formed devices in the well can be isolated from the semiconductor substrate using deeply doped regions which are usually adopted in advanced technologies.

Abstract: The present invention provides a layout structure of an interconnection which feeds a fixed voltage level to a sense amplifier provided in a cell array block of a semiconductor memory device, wherein the interconnection selectively extends only an inside of an outside edge of a second conductivity type outside well region provided along one peripheral side of a first conductivity type well region, in which the cell array block is provided.

Abstract: The present invention prevents a charge-up during a wiring layer etching in a nonvolatile semiconductor storage apparatus having a floating gate and a control gate to which both of positive and negative voltages are applied during a memory cell operation. On a semiconductor substrate 51 of a first conductive type, a first well 52 of a second conductive type is formed to oppose to the first conductive type. In the first well 52, a second well 53 of the first conductive type is formed. On a main surface of the second well 53 is formed a composite gate 8 consisting of a first gate insulation film 4, a floating gate 5, a second gate insulation film 6, and a control gate 7 which are successively layered. On a surface of the second well 53 are formed by way of ion implantation, a source, a drain, and a charge-up preventing element diffusion layer 18 of the second conductive type.

Abstract: A current source formed in a p-type substrate is disclose. First, a deep n-well is formed within the p-type substrate and a buried n+ layer is formed within the deep n-well. Next, a p-well is formed within the deep n-well and atop the buried n+ layer. The p-well and deep n-well are then surrounded by an isolation structure that extends from the surface of the substrate to below the level of the p-well. A n+ reference structure is formed within the p-well and a gate is formed above the p-well, the gate separated from the substrate by a thin oxide layer, the gate extending over at least a portion of the n+ reference structure. Finally, a n+ output structure is formed within the p-well. An input reference current is provided to the n+ reference structure and an output current is provided by the n+ output structure.

Abstract: A nitrogen implanted region formed substantially below and substantially adjacent to a source/drain region of an IGFET forms a liner to retard the diffusion of the source/drain dopant atoms during a subsequent heat treatment operation such as an annealing step. The nitrogen liner may be formed by implantation of nitrogen to a given depth before the implantation of source/drain dopant to a lesser depth. Nitrogen may also be introduced into regions of the IGFET channel region beneath the gate electrode for retarding subsequent lateral diffusion of the source/drain dopant. Such nitrogen introduction may be accomplished using one or more angled implantation steps, or may be accomplished by annealing an implanted nitrogen layer formed using a perpendicular implant aligned to the gate electrode. The liner may be formed on the drain side of the IGFET or on both source and drain side, and may be formed under a lightly-doped region or under a heavily-doped region of the drain and/or source.

Abstract: Impurities are added to a conductor layer in a semiconductor process to prevent formation of void spaces and encourage complete filling of contacts. The impurities reduce the melting point and surface tension of a conductor layer, thereby improving filling characteristics during a reflow step. The impurities may be added at any time during the process, including during conductor deposition and/or reflow.

Abstract: A tub structure underlying a first well in a semiconductor integrated circuit is charge pumped to increase electron collection efficiency in the tub structure. A charge pumping circuit applies the biasing voltage via a second well. The current in the tub structure is monitored to determine when to pump charge into the tub structure. The pumping biases the n-tub to voltages as high as twice the supply voltage magnitude, (2V.sub.cc). The tub current is compared to a minimum current threshold and a maximum current threshold. The charge pump is disabled when the tub current exceeds the maximum threshold and is turned on before the tub current goes below the minimum threshold. The maximum threshold is for keeping the tub structure from exhibiting an undesirable standby current. The minimum threshold is to keep the tub structure biased enough to achieve a desired electron collection efficiency.

Abstract: A semiconductor device include: a substrate of a conductivity type; a first well provided in the substrate and of the same conductivity type as the conductivity type of the substrate; a second well provided in the substrate and of an opposite conductivity type to the conductivity type of the substrate; and a buried well provided at a deep position in the substrate and of the opposite conductivity type to the conductivity type of the substrate. A buried well of the same conductivity type as the conductivity type of the substrate is further provided so as to be in contact with at least a part of a bottom portion of the first well so that the first well is at least partially electrically connected to the substrate.

Abstract: A method is provided for forming a triple well of a semiconductor memory device, where a second well of a second conductive type encloses a second well of a first conductive type. A single mask is used for ion implanting the base of the enclosing well and also the entire enclosed well, which inherently avoids misalignment. Additional doping is provided to the location where the sidewalls of the enclosing well join its base. This is accomplished either by a second, deeper ion implant of the sidewalls, or by ion implanting the base at an angle and rotating it, or both. Alternately, the single mask pattern is processed between the ion implantation steps to alter its width.

Abstract: An ETOX cell that has improved injection of electrons from a forward biased deep n-well to p-well junction underneath the channel area of a triple-well ETOX cell during substrate hot electron (SHE) programming. The ETOX cell has a control gate, a floating gate, a deep n-well formed in the substrate, a buried n+ layer in the deep n-well, a p-well formed in the n-well and atop the buried n+ layer, a drain implant formed in the p-well, and a source implant formed in the p-well. The buried n+ layer enhances the parasitic bipolar action between the n+ source/drain (as collector), the p-well (as base), and the buried n+ layer (as emitter). The parasitic transistor amplifies the amount of seed electrons injected into the p-well, which in turn results in significantly faster programming of the ETOX cell.

Abstract: A semiconductor layer is formed on a semiconductor substrate. A digital circuit region, in which a digital circuit is formed, and an analog circuit region, in which an analog circuit is formed, are separately formed by an isolation region at the surface of the semiconductor layer. At this time, a width of the semiconductor layer in the isolation region is greater than a thickness of the semiconductor substrate. Also, a region having high electrical resistance with low concentration of impurity is formed at the surface of the semiconductor substrate in the isolation region. Furthermore, conductive layers connected to a grounding potential is formed on the backside of the semiconductor substrate in the digital circuit region and on the backside of the semiconductor substrate of the analog region.

Abstract: An RF switch comprises a switching FET having gate and back gate terminals, an input port for receiving an RF signal, and an output port for providing substantially the RF signal during an ON state of the FET. Switching circuitry connects the back gate terminal of the FET to the input port during the ON state to reduce insertion loss during the ON state, and connects the back gate terminal to a point of reference potential during an OFF state of the FET to increase isolation during the OFF state. Preferably, the switching FET is a depletion mode silicon MOSFET capable of operating with low supply voltages. The switching circuitry preferably comprises a second FET for electrically connecting the back gate terminal and the input terminal (e.g., source) of the switching FET during the ON state, and a third FET for electrically connecting the back gate terminal of the switching FET to the point of reference potential during the OFF state.

Abstract: A large sense voltage is produced by the semiconductor device of the present invention. The semiconductor device, utilizing current mirror techniques, is comprised of a power MOSFET having a plurality of power cells and a plurality of sense cells formed in a semiconductor epitaxial layer. The large sense voltage is provided by isolating and separating the plurality of power cells from the plurality of sense cells by at least the thickness of the semiconductor epitaxial layer. Isolation can be provided by forming a plurality of inactive cells or an elongated cell between the plurality of power cells and the plurality of sense cells. In addition, high voltage capabilities can be maintained by including a partially active region adjacent the power cells to provide for good termination.

Abstract: The transistor comprises a buried base P region, a buried emitter N+ region with elongate portions (fingers), deep contact P+ base regions, emitter N+ interconnection regions serving balancing resistor functions, and base, emitter, and collector surface contact electrodes. To provide a higher current gain and a larger safe operation area, with each emitter "finger" there are associated a screening P region interposed between the "finger" and a part of the respective N+ interconnection region, and a contact N+ region which extends to the "finger" and is surface connected to the screening P region by a dedicated electrode.

Abstract: An EEPROM device in which a high voltage is applied to the chip during the memory cell operation and a method for the manufacturing the same are disclosed. On a P-type semiconductor substrate, a first N-well is formed in a surface portion of the substrate in the cell array region and a second N-well is formed in a first surface of the substrate in the peripheral circuit region. An EEPROM memory cell is formed on the first P-well and a first NMOS transistor is formed on the second P-well. Also, a second NMOS transistor is formed on a second surface portion of the semiconductor substrate in the peripheral circuit 10 region and a PMOS transistor is formed on the second N-well. The impurity concentrations of the first and second P-wells are controlled in accordance with the characteristic of the MOS transistors to be formed. Further, a second NMOS transistor having a resistance against a high voltage is directly formed on the P-type substrate. Thus, the electric characteristic of the EEPROM device is enhanced.

Abstract: Disclosed is a semiconductor device, such as a semiconductor memory device, having structure wherein invasion of minority carriers from the semiconductor substrate into components of the device, formed on the substrate, can be avoided. The semiconductor memory device can be an SRAM or DRAM, for example, and includes a memory array and peripheral circuit on a substrate. In one aspect of the present invention, a buried layer of the same conductivity type as that of the substrate, but with a higher impurity concentration than that of the substrate, is provided beneath at least one of the peripheral circuit and memory array. A further region can extend from the buried layer, for example, to the surface of the semiconductor substrate, the buried layer and further region in combination acting as a shield to prevent minority carriers from penetrating to the device elements.

Abstract: A MOS-type semiconductor clamping circuit includes a semiconductor substrate receiving a substrate potential, a well isolated electrically from the substrate potential, and MOS-type transistors formed in the well. Those transistors are connected with each other in series, each transistor has its gate connected to its drain, and a stable potential different from the substrate potential is applied to the well.

Abstract: A high density, mixed technology integrated circuit comprises CMOS structures and bipolar lateral transistors, the electrical efficiency and Early voltage of which are maintained high by forming "well" regions through the collector area. The operation determines the formation of a "collector extension region" extending relatively deep within the epitaxial layer so as to intercept the emitter current and gather it to the collector, subtracting it from dispersion toward the substrate through the adjacent isolation junctions surrounding the region of the lateral bipolar transistor. Under comparable conditions, the ratio between IcIsubstrate is incremented from about 8 to about 300 and the Early voltage from about 20V to about 100V. The V.sub.CEO, BV.sub.CBO and BV.sub.CES voltages are also advantageously increased by the presence of said "well" region formed in the collector zone.