Abstract: A method of forming multi-layer structure of source/drain electrodes and an amorphous silicon layer in a forward staggered thin film transistor. Source/drain electrodes are selectively provided on an insulator. Each of the source/drain electrodes comprises an undoped transparent conductive film on the insulator and an impurity doped transparent conductive film on the insulator and an impurity doped transparent conductive film extending over the undoped transparent conductive film. An amorphous silicon active layer extends over the source/drain electrodes and a top surface of the insulator so that the amorphous silicon active layer over the source/drain electrodes has an impurity diffused interface in contact with the impurity doped transparent conductive film to form ohmic contacts between the impurity doped transparent conductive film and the amorphous silicon active layer.

Abstract: Ultra shallow, low resistance LDD junctions are achieved by forming an LDD implant generating an interstitial-rich section and forming a sub-surface, non-amorphous region generating a vacancy-rich region substantially overlapping the interstitial rich region generated when forming the LDD implant. Embodiments include ion implanting, Ge or Si to form surface amorphous and sub-surface, non-amorphous regions, and implanting B or BF.sub.2 to form the impurity region. Embodiments include forming the sub-surface, non-amorphous region before or after generating the surface amorphous region, and forming the impurity region before or after forming the sub-surface, non-amorphous region but after forming the surface amorphous region.

Abstract: A process of producing a thin film transistor of a liquid crystal display device according to the present invention comprises the steps of forming a semiconductor layer on an insulation substrate, stacking an insulation film and a conductive layer on the semiconductor layer, patterning the conductive layer to form a gate electrode, reducing a width of a mask used at formation of the gate electrode in a prescribed amount to form an offset region, implanting highly concentrated impurity ions into a part of the semiconductor layer where there are not the mask or the conductive layer to form an N.sup.+ -polysilicon layer, re-etching the conductive layer by using the mask used at formation of the gate electrode made narrower by the offset region, and implanting low concentrated impurity ions into the semiconductor layer below the conductor region removed by re-etching to form an N.sup.- -polysilicon layer.

Abstract: A plasma enhanced chemical vapor deposition process for depositing conformal silicon oxide thin films useful to make thin film transistors which have stable electrical properties and low charge centers onto a substrate comprising flowing a precursor gas mixture of silane and nitrous oxide, the latter at a high rate, at a pressure of at least about 0.8 torr and a temperature of from about 250.degree. to 350.degree. C. The effective volume of the reaction region between the gas manifold inlet and the substrate during processing is kept small.

Abstract: The breakdown voltage of a VDMOS transistor is markedly increased without depressing other electrical characteristics of the device by tying the potential of a field-isolation diffusion, formed under the edge portion of a strip of field oxide separating a matrix of source cells from a drain diffusion, to the source potential of the transistor. This may be achieved by extending a body region of a peripheral source cell every given number of peripheral cells facing the strip of field-isolation structure until it intersects said field-isolation diffusion. By so connecting one peripheral source cell every given number of cells, the actual decrement of the overall channel width of the integrated transistor is negligible, thus leaving unaltered the electrical characteristics of the power transistor.

Abstract: In a field intensity relaxation of the drain end of a MOSFET, a projective area is not increased with a reduced electrostatic coupling of the source or drain with the gate. The MOSFET satisfying such condition is fabricated on the SOIS film formed by processes of the lateral vapor phase epitaxial growth and the like. A U-shape low concentration impurity region is provided on a gate electrode through a gate dioxide film and high concentration impurity regions are formed at the tops of protrusions. The gate electrode is embedded in insulation films, and the transistor region is fabricated by the lateral vapor phase epitaxial growth and the like.

Abstract: Self-aligned HFETS are fabricated by providing a semi-insulating substrate and forming a low bandgap III-V semiconductor layer thereon. A first dielectric layer of a first dielectric material is formed on the III-V layer and first and second openings are formed through the first dielectric layer and the III-V layer. After forming dielectric spacers of a second dielectric material on the sidewalls of the first and second openings, gates are formed therein. The first dielectric layer is subsequently removed and source and drain regions are formed in the III-V layer and substrate adjacent to each of the gates. The formation of the source and drain regions is self-aligned to the gates. After forming isolation regions between devices, ohmic contacts to the source and drain regions, all being of a like material, are formed. This formation is also self-aligned to the gates.

Abstract: A micro MIS type FET comprises first conductivity type source/drain regions formed in a surface of a semiconductor layer mutually spaced apart by a distance of less than 2 .mu.m, a second conductivity type channel layer having an impurity concentration of less than 1.times.10.sup.16 /cm.sup.3 formed between the source/drain regions to have a depth less than depths of the source/drain regions, and a second conductivity type threshold voltage control region having an impurity concentration of more than 1.times.10.sup.17 /cm.sup.3 beneath the channel layer.

Abstract: In a method for fabricating a FET of the present invention, first and second side walls are formed on a side surface of a gate electrode, and two n-GaAs layers are formed on an active layer by selective growth using the side walls as a mask. After that, the side walls are removed, whereby double recesses are formed around the gate electrode.

Abstract: An FET with multiple channels to provide a substantially linear transfer characteristic. The widths and carrier concentrations of the channels, and the depths of the channels below the gate of the FET, are adjusted such that a substantially linear gate voltage-to-output current (drain) transfer characteristic of the FET results. In addition, the electrical characteristics of the FET may be adjusted by changing the spacing of the drain and source diffusions from the gate.

Abstract: A method of manufacturing a semiconductor device including a MOS-type field effect transistor includes cleansing a surface of a substrate; forming, next to the cleansing step, a gate oxide film on the cleansed surface of the substrate; wherein the cleansing step includes dry-etching the surface of the substrate in an atmosphere in which hydrogen fluoride and a substance containing at least a chlorine atom coexist in gaseous state and removing an oxide film and metal impurities on the surface of the substrate. Preferably, the dry-etching is performed under heat and decompression.

Abstract: The present invention is a method for making field effect devices, such as a field effect transistors, having ultrashort gate lengths so low as five hundred angstroms or less. In accordance with the invention the gate structure is grown vertically on a substrate by thin film deposition so that the length dimension of the gate is perpendicular to a major surface of the substrate. An edge of the gate-containing substrate is exposed, and the structure comprising the source, drain and channel is grown on the edge. Using this approach, field effect devices with precisely controlled gate lengths of less than 100 angstroms are achievable. Moreover the active regions of the device can be immersed within semiconductor material so that surface properties do not deteriorate device performance.

Abstract: A method for connecting different conducting layers of a microelectronic device is disclosed.

Abstract: In some circuitry, field effect transistors are produced by employing polycrystalline conductive regions including the channel and connections to the source and drain. Conventional methods for producing such transistors involve depositing a thin polycrystalline channel region, patterning this region overlying the patterned region with an insulator, producing openings in the insulator for contacts to source and drain, and depositing a thick polycrystalline contact region. Processing complexity is, however, substantially reduced by first forming interconnect areas, source region and drain regions; then opening a region for the channel; and finally depositing a layer to form the channel. Thus, at least three processing steps are eliminated and vertical dimensions are reduced.

Abstract: A field effect transistor having regions (20, 20', and 20") which respectively function as a planar elevated surface for gate, drain, and source electrical contact, and method of fabrication. The transistor overlies a substrate (12) and is formed partially from active areas (14 and 14'). The regions (20, 20', and 20"), each underlie or are surrounded by a dielectric layer (22). A gate is formed by a gate layer (24). A source (30) is formed within region (20") and is electrically connected to active area (14'). A drain (30') and channel region are formed within region (20'). Electrical contact is made to the source (30), drain (30') and gate layer (24) by conductive layers (34", 34', and 34, respectively).

Abstract: A method for manufacturing a semiconductor apparatus, providing steps of (i) laminating a first polysilicon layer on the whole surface of a semiconductor substrate through a first oxide layer, (ii) removing the first polysilicon layer and first oxide layer in an element separation region so as to form a trench therein and to treat the residual first polysilicon layer and first oxide layer as a bottom gate electrode and an insulating film respectively, (iii) forming a monocrystalline silicon layer by epitaxial growth on the whole surface of the semiconductor substrate including the trenches, (iv) removing the monocrystalline silicon layer in the element separation region, laminating a second oxide layer on the whole surface of the semiconductor substrate including the removing portion, and making the second oxide layer remain as an element separation film in only the element separation region, and (v) forming a gate oxide film and a top gate electrode on the residual monocrystalline silicon film, and forming a

Abstract: A thin film field effect transistor has an island of polysilicon on the surface of a substrate, preferably of an insulating material. A layer of silicon dioxide is on the surface of the substrate and surrounds the polysilicon island. The silicon dioxide layer is of substantially uniform thickness and contacts the edge of the polysilicon island. A gate insulator layer, preferably of silicon dioxide, of substantially uniform thickness is on the surface of the polysilicon island. A conductive gate, preferably of doped polysilicon, is on the gate insulator layer and extends across a portion of the polysilicon island. The portions of the polysilicon island at opposite sides of the gate are doped to form the source and drain of the transistor. The transistor is formed by applying a layer of polysilicon on the surface of a substrate and applying a mask over the portion of the polysilicon layer which is to form the island.

Abstract: A method of fabricating heterojunction structures includes providing a semiconductor substrate and forming a plurality of semiconductor layers thereon. Ohmic and gate contacts are then formed on the plurality of semiconductor layers and portions of at least one of the semiconductor layers disposed between the ohmic and gate contacts are removed. Gate metal is then formed on the gate contacts. Source and drain regions are formed in the semiconductor layers and the formation is self-aligned to the gate metal. Following the formation of the source and drain regions, ohmic metal is formed on the ohmic contacts.

Abstract: A method of producing an improved field effect transistor integrated circuit device in a semiconductor substrate embodying a first type dopant and having a recessed gate electrode and self-aligned source and drain regions can be made. A first masking layer is formed on the surface of said semiconductor substrate that is capable of masking the underlying silicon against oxidation. Portions of first masking layer is removed to form openings that at least define the gate electrode regions. The resultant exposed silicon area are oxidized to produce a thick sunken silicon oxide layer. The first masking layer is removed. A second opposite type dopant is introduced into the substrate on opposite sides of the sunken thick oxide layer that defines the region of the gate electrode to form source and drain regions. The sunken thick oxide layer is selectively removed, thereby forming a depression in the substrate that defines the gate region.

Abstract: A semiconductor device comprising three recessed portions formed at a very small pitch on the surface of a semiconductor substrate, remaining regions formed between these recessed portions as impurity diffused regions serving as the source and the drain, respectively, and a conductive region as a gate electrode formed through an insulating film within the central recessed portion, and a method of manufacturing such a semiconductor device are disclosed. With this device, its gate length can be made shorter than that in the prior art and the junction leakage is reduced, resulting in miniaturization and an improvement in the characteristics.

Abstract: A permeable base transistor (30) including a metal base layer (34) embedded in a semiconductor crystal (32) to separate collector (38) and emitter (40) regions and form a Schottky barrier with each is disclosed. The metal base layer has at least one opening (37) through which the crystal semiconductor (32) joins the collector (38) and emitter (40) regions. Ohmic contacts (42,44) are made to the emitter (38) and collector (40) regions. The width of all openings (37) in the base layer (34) is of the order of the zero bias depletion width corresponding to the carrier concentration in the opening. The thickness of the metal layer (34) is in the order of 10% of this zero bias depletion width. As a result, a potential barrier in each opening limits current flow over the lower portion of the bias range.

Abstract: In a monolithic OEIC in which an FET and a light-emitting device are integrated, the light-emitting device has a first clad layer, an active layer, and a second clad layer stacked on a substrate, the FET has a channel layer and source and drain layers with a high impurity concentration stacked on the substrate, etching mask layers on the source and drain layers, and a gate electrode formed on a channel layer between source and drain electrodes and the source and drain layers, the first clad layer of the light-emitting diode and the source and drain layers with a high impurity concentration of the FET are formed of the same semiconductor layer, and an active layer of the light-emitting device and the etching mask layers of the FET are formed of the same semiconductor layer.

Abstract: A process for forming MOS devices having graded source and drain regions. The source and drain regions are lightly doped by ion implantation and then subjected to thermal cycling to diffuse the implanted impurities. The source and drain regions are then heavily doped to form source and drain regions having a heavily doped subregion and a lightly doped subregion. Devices made pursuant to the process, which can be made less than one-half micron, are not subject to gate oxide charging and have high snapback voltages.

Abstract: A T-shaped gate of an FET is formed by utilizing the image reverse photolithography process, which includes coating of a semiconductor substrate with a positive resist, initial exposure of an resist outside region, reversal baking, flood exposure of the entire resist layer, and development of the resist layer. The image reverse photolithography process is performed after a dummy gate is formed on the semiconductor substrate. By properly adjusting a light quantity of the flood exposure, a resist pattern can be obtained which has a center hole whose boundary surface is inclined inwardly, and whose bottom surface defines a bottom resist layer thinner than the dummy gate. After removing the dummy gate, a gate material is deposited and then the resist pattern is removed to leave the T-shaped gate.

Abstract: An improved masking stack (63) comprises a pad oxide (58), polysilicon (60) and nitride (62). After forming a photoresist pattern (64) over the stack (63), an anisotropic etch is performed to remove the nitride (62) and a portion of the polysilicon (60) not covered by the pattern (64). Another etch is performed to remove the remaining polysilicon (60) to leave at least a portion of the pad oxide (58). A boron implant (66) is conducted to form implant areas (68 and 70) within the unmasked silicon active device layer (56). A portion of the implant areas (68 and 70) is masked with nitride (72), and the unmasked silicon layer (56) is then etched. The masking stack (63) and the nitride (72) is removed and unprotected silicon layer (56) and implant areas (68 and 70) are covered with an oxide forming the silicon dioxide mesa (78).

Abstract: A process for making an inverted silicon-on-insulator semiconductor device having a pedestal structure. After the processing of polysilicon layers, dielectric layers, an epitaxial region and a nitride layer, a second substrate is bonded to the nitride layer and the first substrate is removed. This allows for an epitaxial region which is isolated from the substrate.

Abstract: Certain semiconductor device structures are described in which single crystal layers of cubic Group II fluorides cover at least part of the surface of III-V semiconductor compound. The fluoride crystal has a cubic structure and may be lattice matched or lattice mismatched to the compound semiconductor substrate depending on fluoride composition. These fluoride single crystal layers are put down by a moleuclar beam epitaxy procedure using certain critical substrate temperature ranges and a particular cleaning procedure.

Abstract: A process for fabricating complimentary semiconductor devices having pedestal structures wherein both PNP and NPN transistors are formed simultaneously on the same substrate. After polysilicon layers have been patterned and etched, various polysilicon regions are doped with a plurality of conductivity types. This allows for there to be both P+ and N+ regions in the same polysilicon layer thereby enabling complimentary PNP and NPN transistors to be formed using a limited number of processing steps.

Abstract: A method of manufacturing an insulated-gate field effect transistor is comprised of forming on a semiconductor substrate a gate electrode elecrically insulated from the substrate. A flat insulating film of silicon oxide is formed over the substrate. A pair of openings are formed through the flat insulating film at both sides of the gate electrode such that opposite side thereof are etched and exposed. An oxide film is formed on the exposed side edges of the gate electrode. Impurities are implanted through the pair of openings into the substrate to form source and drain regions. An electroconductive polysilicon film is deposited over the substrate. The deposited polysilicon film is polished to leave a part thereof selectively in the openings to thereby form electrical contacts to the source and drain regions through the openings.

Abstract: The fabrication of high performance and reliable Buried Channel Field Effect Transistor (BCFET) using Schottky gate junction and heavily doped N layers for the source and drain electrode is described. The BCFET is composed of a semi-insulating substrate in which two N layers for the drain electrodes and one N layer for the source electrode are formed in one of the semi-insulating surface. The N source electrode is centrally located between the two N drain electrodes and all three lie in the same plane. The source and drain electrodes are separated by a thin semi-insulating layer, the length of which can range from 0.5 micron to several micron range, depending on the desired voltage breakdown. A Schottky gate is defined in an active N layer directly above the source N Layer. The ohmic contacts for the source and drain N layers are defined several microns away from the schottky junction, resulting in a considerable improvement in device reliability.

Abstract: A method of forming metal oxide semiconductor field-effect transistors (MOSFET) is described wherein the source and drain regions are disposed by ion implantation in a manner substantially perpendicular to the substrate surface in two steps, such that the concentration of impurities increases with lateral distance away from the gate electrode member to suppress the hot e injection, to prevent channeling effect, to increase punch through voltage and to increase gate-aided breakdown voltage.

Abstract: A process for producing a semiconductor device includes depositing a layer of insulator material onto a supporting substrate of the type having a surface which includes a channel region below the surface thereof containing a carrier concentration of a desired conductivity type, removing selected portions of the insulator material to form a substitutional gate on the substrate surface, forming side walls bounding substitutional gate to define an effective masking area in cooperation with the substitutional gate, ion implanting a dopant into the unmasked region of the substrate, removing the side walls, annealing the resultant device, removing the substitutional gate, depositing gate metal and first and second ohmic contacts in correct positional relation to one another on the substrate, and depositing metallic interconnects in electrical communication with the ohmic contacts to produce a semiconductor device.

Abstract: A method of forming metal oxide semiconductor field-effect transistors (MOSFET) is described wherein the source and drain regions are disposed by ion implantation in a manner substantially perpendicular to the substrate surface in two steps, such that the concentration of impurities increases with lateral distance away from the gate electrode member to suppress the hot e injection, to prevent channeling effect, to increase punch through voltage and to increase gate-aided breakdown voltage.

Abstract: The fabrication of high performance and reliable Buried Channel Field Effect Transistor (BCFET) using Schottky gate junction and heavily doped N layers for the source and drain electrode is described. The BCFET is composed of a semi-insulating substrate in which two N layers for the drain electrodes and one N layer for the source electrode are formed in one of the semi-insulating surface. The N source electrode is centrally located between the two N electrodes and all three lie in the same plane. The source and drain electrodes are separated by a thin semi-insulating layer, the length of which can range from 0.5 micron to several micron range, depending on the desired voltage breakdown. A Schottky gate is defined in an active N layer directly above the source N layer. The ohmic contacts for the source and drain N layers are defined several microns away from the Schottky junction, resulting in a considerable improvement in device reliability.

Abstract: Herein disclosed is a semiconductor device in which control means for carriers migrating in a first semiconductor includes an interface state layer lying on the first semiconductor and a second conductor layer lying on the interface state layer. The interface state layer has its Fermi level pinned to that of the second semiconductor layer. By thus constructing an FET or the semiconductor device, an inversion or accumulation layer can be easily formed in the interface merely by applying a voltage to the control means.

Abstract: A field effect transistor is disclosed similar to a junction field effect transistor, but in which the depletion width in the channel due to a PN junction adjoining the channel is controlled not by directly controlling the reverse voltage on the PN junction, but by reverse biasing a second PN junction such that the depletion region from the second PN junction meets the depletion region from the first PN junction (on the side other than the channel side) to thus restrict the width of the depletion regions due to the first PN junction.

Abstract: An insulated-gate semiconductor device, such as an IGFET or IGT, with improved source-to-base shorts includes, in a semiconductor wafer, a drain region, a voltage-supporting region, a base region, and a source region. Generally parallel gate fingers of refractory material are insulatingly spaced above the wafer. Elongated base portions are provided between, and preferably registered to, a respective pair of adjacent gate fingers. Elongated source portions are each situated within a respective base portion and each is preferably registered to a respective pair of adjacent gate fingers. Generally parallel shorting portions are included in the wafer and are oriented transverse to the gate fingers, whereby the shorting portions can be formed without a critical alignment step. The shorting portions adjoin the base portions and also a source electrode so as to complete source-to-base electrical shorts.

Abstract: The fabrication of high performance and reliable Buried Channel Field Effect Transistor (BCFET) using Schottky gate junction and heavily doped N layers for the source and drain electrode is described. The BCFET is composed of a semi-insulating substrate in which two N layers for the drain electrodes and one N layer for the source electrode are formed in one of the semi-insulating surface. The N source electrode is centrally located between the two N drain electrodes and all three lie in the same plane. The source and drain electrodes are separated by a thin semi-insulating layer, the length of which can range from 0.5 micron to several micron range, depending on the desired voltage breakdown. A Schottky gate is defined in an active N layer directly above the source N layer. The ohmic contacts for the source and drain N layers are defined several mcirons away from the Schottky junction, resulting in a considerable improvement in device reliability.

Abstract: A semiconductor device is manufactured by forming a first insulating film on a surface of a semiconductor substrate of a first conductivity type, and a first nonmonocrystalline silicon film is formed on the first insulating film. A second insulating film is deposited on the first nonmonocrystalline silicon film by CVD, sputtering or molecular beam method. An impurity is then ion-implanted in the first nonmonocrystalline silicon film through the second insulating film. The second insulating film is then removed to expose the surface of the first nonmonocrystalline silicon film doped with the impurity, and a thermal oxide film is formed on the exposed portion of the first nonmonocrystalline silicon film. Subsequently, a second nonmonocrystalline silicon film is formed on the thermal oxide film, and a third insulating film is formed on the second nonmonocrystalline silicon film.

Abstract: The specification describes a high capacity nonvolatile CCD read only memory system that includes a plurality of memory cells. Selected ones of the memory cells include a double-diffused region having a first and second implant or diffusion under a clocked electrode whereby the first implant or diffusion provides a fixed charge required for ROM operation and the charge and polarity of said second implant or diffusion provides a neutralizing effect on the surface potential under the clocked electrode and above the double implanted or double diffused region.

Abstract: A method is provided for manufacturing a reference voltage generator device which detects a voltage corresponding to an energy gap of a semiconductor, or a voltage of a value close thereto, or a voltage based on an energy level of a semiconductor, and generates the detected voltage as a reference voltage. The reference voltage is generated by detecting a difference of threshold voltages of first and second insulated gate field-effect transistors (IGFETs). Gate electrodes of the first and second IGFETs are formed on gate insulating films which are formed on different surface areas of an identical semiconductor substrate under substantially the same conditions.

Abstract: A process for making a CMOS dual-well semiconductor structure with field isolation doping, wherein only a single lithographic masking step is required for providing self-alignment both of the wells to each other and also of the field isolation doping regions to the wells. The lithographic masking step forms a well mask and defines an oxidation barrier which acts as: an implant mask (absorber) during the ion-implantation of a field dopant of one type; an oxidation barrier over one well during the oxidation of the opposite-type well to form over the one well a sacrificial oxide layer which forms the alignment marks for subsequent formation of the field-doping regions; and a dopant-transmitter during the ion-implantation of an opposite-type field dopant which is simultaneously absorbed by the sacrificial oxide. As a result, there are formed field-doped oxide layers self-aligned to the wells so that, with a subsequent masking step, oxide field isolations are defined over the doped oxide layers.

Abstract: To minimize the number of independent masking operations in the manufacture of a CMOS integrated circuit device using twin tub technology, the n-tub is made by separate phosphorus and arsenic implants through a common mask, and the p-tub is made by two separate boron implants through a common mask, complementary to that used for forming the n-tub. One of the boron implants occurs before, the other after, the drive-in heating step. After tub formation, further movement of the implanted ions is kept small by use of a high pressure process for growing the field oxide and by only limited further heating. Transistors are then formed in the tubs.