Abstract: The method includes forming a buried oxide layer in a substrate. A pad oxide layer is then formed on the substrate. A silicon nitride layer is pattered on the surface of the pad oxide. Then, a thick field oxide (FOX) is formed on the pad oxide layer. Sidewall spacers are formed on the side walls of the opening of the silicon nitride layer. Next, the FOX is etched. An ion implantation is performed for adjusting the threshold voltage and anti-punch-through implantation. Subsequently, a dielectric with high permittivity is deposited along the surface of the substrate. The dielectric layer may be formed by a nitride technique. A conductive layer composed of metal or alloy is then formed on the dielectric layer and refilled into the opening. A chemical mechanical polishing is used to remove the dielectric layer, silicon nitride and the spacers such that the conductive layer remains only in the opening. The residual nitride and spacers are removed by hot phosphor acid solution. Source and drain are next created.

Abstract: A static random access memory device includes: a semiconductor substrate divided into a cell array portion and a periphery circuit portion; a first insulating layer for insulating devices formed on the substrate from a thin-film transistor; a conductive layer formed on the first insulating layer in the cell array portion, for supplying power; a buffer layer formed on the conductive layer in the cell array portion; a second insulating layer formed on the buffer layer in the cell array portion and on the first insulating layer of the periphery circuit portion; and a metal wiring pattern formed on the second insulating layer. A first portion of the metal wiring pattern connects to the conductive layer via a first contact hole which is formed passing through the second insulating layer and the buffer layer, thus exposing the conductive layer in the cell array portion.

Abstract: The present invention is directed to a new and improved technique for formation of metal oxide semiconductor field effect transistors. In particular, the method involves formation of an initial gate structure that is wider than the desired final channel length of the completed transistor. Thereafter, an initial heavy-doping step is applied to the drain and source regions of the device. The width of the gate structure is then patterned and etched back to the desired final channel length of the device. A second, light-doping LDD implant is performed to complete the source and drain regions of the finished device.

Abstract: A method for fabricating a semiconductor device having LDD structure. The method includes: a first step for forming an electrically insulating layer on an active area defined on a surface of a semiconductor substrate; a second step for forming a conductive layer on said insulating layer; a third step for forming a patterned photoresist layer of a downward tapered shape on said conductive layer; a fourth step for forming a gate electrode by patterning said conductive layer using a mask provided by bottom portions of said patterned photoresist layer; a fifth step for forming heavilyly doped regions at both sides of said gate electrode by introducing ions using a mask provided by top portions of said patterned photoresist layer; a sixth step for removing said patterned photoresist layer; and a seventh step for forming lightly doped regions at both sides of said gate electrode by introducing ions using a mask provided by said gate electrode.

Abstract: A method for fabricating a high-voltage device substrate comprising the steps of forming a pad oxide layer and a mask layer over a substrate. Then, the pad oxide layer and the mask layer are patterned to define a region for a first ion implantation. Next, the exposed substrate is oxidized to form a field oxide layer. Thereafter, the mask layer is removed followed by a first ion implantation. Next, the field oxide layer is completely removed. Subsequently, a photoresist layer is formed over the first ion implanted region. This is followed by a second ion implantation. Then, a conformal oxide layer is formed covering the substrate surface. Next, a high temperature drive-in and oxidation operation is carried out, in which ions in the first ion implanted region and the second ion implanted region are driven deeper into the substrate interior, and at the same time the substrate above those regions are oxidized.

Abstract: A semiconductor processing method of providing electrical isolation between adjacent semiconductor diffusion regions of different field effect transistors includes, a) providing an electrically insulative device isolation mass between opposing active area regions, the insulative isolation mass having opposing laterally outermost edges; and b) providing a pair of electrically conductive transistor source/drain diffusion regions within the active area regions, one of the conductive source/drain diffusion regions being received within one of the active area regions and being associated with one field effect transistor, the other of the conductive source/drain diffusion regions being received within the other of the active area regions and being associated with another field effect transistor, the electrically conductive source/drain diffusion regions each having an outermost edge adjacent the insulative isolation mass, such source/drain diffusion regions edges being received within the respective active area reg

Abstract: A transistor and transistor fabrication method are presented in which a graded junction is formed using a plurality of source/drain dopant implants. The implants are performed such that higher concentrations of dopant species are implanted at lower energies and lower dopant concentrations are implanted at higher energies. In an embodiment, an anneal step is used to create the graded junction by exploiting the concentration dependence of the dopant diffusivity (i.e., dopant species implanted in regions of high concentration are more mobile than dopant species implanted in regions of low concentration). Sub-0.25-micron transistors formed by the process described herein may be less susceptible to deleterious capacitive loading and parasitic resistance than transistors having conventionally formed lightly doped drain and source/drain implants.

Abstract: A method is provided for forming self-aligned silicide in integrated circuit, which can help prevent the occurrence of a bridging effect in the integrated circuit. This method is characterized in the provision of an elevated spacer structure that can act like a barrier to prevent the occurrence of a bridging effect between the polysilicon gate and the source/drain regions caused by the forming of undesired silicide over the spacer structure due to lateral diffusion of the silicide from the polysilicon gate. Moreover, this method is characterized in the use of two different materials to respectively form the sacrificial layer and the field oxide layers, thus allowing the field oxide layers to remain substantially intact during the removal of the sacrificial layer through etching. This feature can help prevent the occurrence of leakage current from the metal plug to the substrate.

Abstract: A method is provided for fabricating a thin film transistor on a substrate. The method includes the steps of forming an active layer having a channel region on the substrate, forming an impurity-blocking mask covering the channel region and portions of the active layer outside the channel region adjacent the channel region, and doping impurities of a first conductivity type at a high density into portions of the active layer uncovered by the impurity-blocking mask to form impurity-doped regions in the active layer. The method further includes the steps of removing the impurity-blocking mask and thereafter performing a plasma treatment on the resultant structure using a plasma gas containing impurities of the first conductivity type to form LDD regions in the active layer between the channel region and the impurity-doped regions.

Abstract: A CMOS semiconductor device having NMOS source/drain regions formed using multiple spacers has at least one NMOS region and at least one PMOS region. A first n-type dopant is selectively implanted into an NMOS active region of the substrate adjacent a NMOS gate electrode to form a first n-doped region in the NMOS active region. A first NMOS spacer is formed on a sidewall of the NMOS gate electrode and a first PMOS spacer on a sidewall of a PMOS gate electrode. A second n-type dopant is selectively implanted into the NMOS active region using the first NMOS spacer as a mask. A p-type dopant is selectively implanted into a PMOS active region using the first PMOS spacer as a mask to form a first p-doped region in the PMOS active region. A second NMOS spacer and a second PMOS spacer are formed adjacent the first NMOS spacer and first PMOS spacer, respectively.

Abstract: Lightly doped regions are implanted into an amorphous region in the semiconductor substrate to significantly reduce transient enhanced diffusion upon subsequent activation annealing. A sub-surface non-amorphous region is also formed before activation annealing to substantially eliminate end-of-range defects on crystallization of amorphous region containing the lightly doped implants.

Abstract: A process is provided for fabricating a transistor in which ion implantation of dopant into source/drain junctions is performed prior to defining the sidewall surfaces of a gate conductor. As such, the sidewall surfaces of the gate conductor are not subjected to damaging bombardment by ions. In one embodiment, a masking layer is patterned above a polysilicon layer dielectrically spaced above a semiconductor substrate. A S/D implant self-aligned to the sidewall surfaces of the masking layer is performed. Portions of the masking layer are removed to reduce the width of the masking layer and to form more closely spaced sidewalls. An LDD implant self-aligned to the new sidewalls of the masking layer is performed. Thereafter, the polysilicon layer is etched to define a gate conductor above and between LDD areas disposed within the substrate. In another embodiment, a sacrificial layer is patterned above a polysilicon layer dielectrically spaced above a semiconductor substrate.

Abstract: A method (100) of forming a transistor (50, 80) includes forming a gate oxide (120) over a portion of a semiconductor material (56, 122) and forming a doped polysilicon film (124) having a dopant concentration over the gate oxide (122). Subsequently, the doped polysilicon film (124) is etched to form a gate electrode (52) overlying a channel region (58) in the semiconductor material (56, 122), wherein the gate electrode (52) separates the semiconductor material into a first region (60) and a second region (68) having the channel region (58) therebetween. The method (100) further includes forming a drain extension region (64) in the first region (60) and a source extension region (72) in the second region (68), and forming a drain region (62) in the first region (60) and a source region (70) in the second region (68). The source/drain formation is such that the drain and source regions (62, 70) have a dopant concentration which is less than the polysilicon film (124) doping concentration.

Abstract: An N-type impurity is ion-implanted in the exposed surface of a semiconductor substrate, thereby forming N-type diffusion layers. A P-type impurity is ion-implanted in the semiconductor substrate covered with a cover film, thereby forming P-type diffusion layers. A compound film of a semiconductor and a metal is formed on each of the surfaces of the N-type and P-type diffusion layers.

Abstract: An asymmetrical N-channel IGFET and a symmetrical P-channel IGFET are disclosed. The N-channel IGFET includes heavily doped and ultra-heavily doped source regions, and lightly doped and heavily doped drain regions. The P-channel IGFET includes lightly doped and heavily doped source and drain regions.

Abstract: A CMOS device and a method for forming the same is provided so as to overcome the problem of boron penetration through the thin gate oxide of P-channel devices. Silicon is implanted into the polysilicon gate electrode of the PMOS device functioning as a diffusion barrier for preventing boron penetration through the thin gate oxide and into the semiconductor substrate. As a result, the reliability of the CMOS device will be enhanced.

Abstract: Field effect transistors having tapered gate electrodes include a body region of first conductivity type extending to a surface of a semiconductor substrate. Source and drain regions of second conductivity type are formed in the substrate and a gate electrode is formed on a portion of the surface extending opposite the body region and between the source and drain regions. A gate electrode insulating layer is also disposed between the gate electrode and the surface. To improve the transistor's withstand voltage capability by reducing field crowding, the gate electrode insulating layer is preferably formed to have a tapered thickness which increases in a direction from the source region to the drain region, and to reduce on-state resistance the drain region is formed in a self-aligned manner to the gate electrode.

Abstract: A process for forming a borderless contact opening to an active device region, overlaid with a metal silicide layer, has been developed. The borderless contact opening is formed in a composite insulator layer, comprised with an overlying, thick ILD layer, and a thin, underlying silicon oxynitride layer. The thin silicon oxynitride layer, used as a etch stop layer, during the anisotropic RIE procedure used to form the borderless contact opening, is deposited at a temperature below 350.degree. C., to prevent agglomeration of the metal silicide layer.

Abstract: In this invention a second gate is created in the area of the drain of a host transistor. The second gate overlies an N-well region and separates the drain of the host transistor into two portions. One portion of the drain is between the field oxide and the second gate and contains the contact for the drain. The second portion of the drain lies between the first gate which controls current in the drain and the second gate. The second gate provides a mask for the siliciding of the drain and provides a high impedance to drain current. In the event of an ESD, drain current is forced down into the N-well through one portion of the drain, under the second gate, and back up through the second portion of the drain providing a longer path and additional bulk material into which to dissipate the energy from an ESD event. Without using an extra mask to block the silicide, the second gate provides a silicide blocking effect to the drain of the ESD protection device.

Abstract: An asymmetrical transistor, and a gate conductor used in forming that transistor, are provided. The gate conductor is formed by removing upper portions of the gate conductor along an elongated axis which the gate conductor extends. The removed portions presents a partially retained region of lesser thickness than the fully retained region immediately adjacent thereto. An implant is then forwarded to the substrate adjacent and partially below the gate conductor. Only the partially retained portions allow a subset of the originally forwarded ions to pass into the substrate to form a lightly doped drain (LDD) between the channel and the drain. The partially retained region occurs only near the drain and not adjacent the source so that the LDD area is self-aligned between the edge of the conductor and a line of demarcation separating the fully retained portion and the partially retained portion.

Abstract: A method of fabricating a semiconductor device and the device. There is provided a substrate (21) of semiconductor material. A gate electrode (25) is formed over the substrate (21) having a sidewall (27) and electrically isolated from the substrate. Source/drain regions (29, 31) are formed in the substrate defining a channel in the substrate extending beneath the gate electrode. One of a pocket region or a halo region (33) extending substantially entirely under the gate electrode and sidewall is then formed. The pocket region or halo region is formed by providing a compensating species which is implanted at the time of the source/drain implant in order to compensate the doping increase under the source/drain caused by the pocket or halo implant. Since the implant dose and range of this compensating implant is comparable to the pocket or halo implant, no penetration of the gate electrode should occur.

Abstract: A method of making an IGFET with a selectively doped channel region is disclosed. The method includes providing a semiconductor substrate with a device region, forming a gate over the device region, forming a masking layer that partially covers the gate and the device region, implanting a dopant into portions of the gate and the device region outside the gate that are not covered by the masking layer, transferring the dopant through the uncovered portion of the gate into a portion of an underlying channel region in the device region, thereby providing the channel region with a non-uniform lateral doping profile and adjusting a threshold voltage, and forming a source and a drain in the device region. The dopant can be implanted through the portion of the gate into the portion of the channel region, or alternatively, the dopant can be diffused from the portion of the gate into the portion of the channel region.

Abstract: A low voltage field effect transistor structure (20) is provided with a threshold voltage that is tolerant of process variations that alter the location of a source implant region (41). A first halo region (33) and a second halo region (36) are formed adjacent to source region (41) such that after subsequent thermal processing, a constant doping profile of opposite conductivity as source region (41) is formed in the channel region (23) adjacent the source region (41). The embodiments can be formed either adjacent to only the source region (41) to create a unilateral device, or the doping profile can be formed adjacent to both source region (41) and a drain region (40) to produce a bilateral device. An additional embodiment forms a second implant region in source region (41) to reduce junction leakage and capacitance.

Abstract: A method of making a lightly doped drain transistor includes the steps of forming a gate electrode (52) and a gate oxide (54) over a semiconductor substrate (56) and forming a drain (70) in a drain region (58) and a source (72) in a source region (60) of the substrate (56). The method further includes generating interstitials (62) near a lateral edge of at least one of the drain (70) and the source (72) and thermally treating the substrate (56). The thermal treatment cause the interstitials (62) to enhance a lateral diffusion (84) of the drain (70) under the gate oxide (54) without substantially impacting a vertical diffusion (82) of the drain (70) or the source (72). The enhanced lateral diffusion (84) results in the formation of at least one of a lightly doped drain extension region (75) and a lightly doped source extension region (76) without an increase in a junction depth of the drain (70) or the source (72).

Abstract: First, a field oxide region, a pad oxide layer and a first nitride layer are formed on a silicon substrate, respectively. Then, a portion of the first nitride layer is removed. A first oxide layer and a nitride spacer are formed on the substrate, respectively. Portions of the first oxide layer and the pad oxide layer are removed to form a first region of the first oxide layer and a second region of the first oxide layer. Then, an ion implantation is performed to form a punch-through stopping region. Next, a second oxide layer and an amorphous-Si layer are formed on the substrate, respectively.Portions of the a-Si layer are etched back. Next, the first nitride layer and the nitride spacer are removed. An ion implantation is performed to form a source, a drain and a doped region at the bottom of the second region of the first oxide layer. Then, a Rapid Thermal Process is used to drive dopant diffusion to form an extended source/drain junction.

Abstract: A semiconductor device having shallow junctions is provided by providing a semiconductor substrate having source and drain regions and polysilicon gate regions; depositing selective silicon on the source and drain regions and on the polysilicon gate regions; providing dopant into the source and drain regions forming shallow junctions; forming first insulating spacers on sidewalls of the gate regions; forming second insulating sidewall spacers on the first insulating spacers; implanting dopants into the source and drain regions for providing deep junctions and into the polysilicon gate regions; and siliciding the top surfaces of the source and drain regions and polysilicon gate regions.

Abstract: A new method of forming an improved buried contact junction is described. A gate silicon oxide layer is provided over the surface of a semiconductor substrate. A polysilicon layer is deposited overlying the gate oxide layer. A hard mask layer is deposited overlying the polysilicon layer. The hard mask and polysilicon layers are etched away where they are not covered by a mask to form a polysilicon gate electrode and interconnection lines wherein gaps are left between the gate electrode and interconnection lines. A layer of dielectric material is deposited over the semiconductor substrate to fill the gaps. The hard mask layer is removed. The polysilicon layer is etched away where it is not covered by a buried contact mask to form an opening to the semiconductor substrate. Ions are implanted to form the buried contact.

Abstract: A manufacturing process in which semiconductor transistors are fabricated using a fluorine or nitrogen implant into the n-channel regions and an amorphization implant to beneficially limit the spreading of the source/drain impurity distributions thereby decreasing the junction depth and increasing the sheet resistance of the source/drain regions. Broadly speaking, a gate dielectric layer is formed on a semiconductor substrate. First and second conductive gate structures are then formed on an upper surface of the gate dielectric layer. The first conductive gate is positioned over the p-well region while the second conductive gate is positioned over the n-well region. An n-channel mask is then formed on the substrate and a first impurity distribution is introduced into the p-well regions. The first impurity distribution preferably includes a species of fluorine or nitrogen. A n-type impurity distribution is then introduced into the p-well regions of the semiconductor substrate.

Abstract: Broadly speaking, the present invention contemplates a semiconductor manufacturing process in which LDD regions of a semiconductor transistor are implanted after the heavily doped regions without requiring the removal of spacer structures from the sidewalls of the transistor gate. A semiconductor substrate is provided. The semiconductor substrate includes a channel region laterally displaced between first and second lightly doped regions. The first and second lightly doped regions are laterally displaced between first and second heavily doped regions of the semiconductor substrate. A gate dielectric is formed on an upper surface of the semiconductor substrate. A conductive gate structure is then formed on the gate dielectric. The conductive gate structure is aligned over the channel region of the semiconductor substrate. First and second spacer structures are then formed on first and second sidewalls of the conductive gate.

Abstract: There is provided a semiconductor device including a transistor, said transistor having (a) a semiconductor substrate, (b) source and drain regions formed in the semiconductor substrate, (c) a gate electrode formed on the semiconductor substrate between the source and drain regions, (d) a silicide layer formed partially on one of the source and drain regions, and (e) an electrode terminal making contact with the silicide layer. The silicide layer extends so that it covers at least an area through which the electrode terminal makes contact with the drain region. In the above mentioned semiconductor device, since the silicide layer is formed only in the vicinity of an area through which the electrode terminal makes contact with the silicide layer, it is possible to construct an output transistor in LDD structure. Thus, there can be obtained an output transistor having higher ESD immunity, higher driving ability, and higher integration.

Abstract: A method of fabricating an integrated circuit transistor in a substrate is provided. A gate electrode stack is formed on the substrate. The stack has a first insulating layer, a first conductor layer on the first insulating layer, a second insulating layer on the first conductor layer, and a second conductor layer on the second insulating layer. First and second source/drain regions are formed in the substrate in spaced apart relation to define a channel region underlying the first insulating layer. First and second sidewall spacers are formed adjacent to the gate electrode stack. The second conductor layer and the second insulating layer are sacrificed and a silicide layer is formed on the first conductor layer. The void remaining after removal of the second conductor and insulating layers establishes a large separation between the silicide forming titanium layer and the first conductor layer. The result is a gate electrode stack that is resistant to lateral silicide formation due to silicon diffusion.

Abstract: A semiconductor fabrication process in which nitrogen is incorporated into the transistor gate without significantly increasing the resistivity of the source/drain region. The incorporation of nitrogen into the gate structure substantially reduces the migration of impurity dopants from the silicon gate into the transistor channel region resulting in a more stable and reliable transistor. In one embodiment, a tail of the nitrogen impurity distribution incorporated into the gate structure extends into the channel region of the semiconductor substrate. In this embodiment, the nitrogen within the channel region prevents excessive lateral diffusion of source/drain impurities thereby permitting the fabrication of deep sub-micron transistors.

Abstract: A method of forming high voltage device. A first type semiconductor having at least a gate formed thereon is provided. A first ion implantation with a second type dopant is performed to form a first diffusion region in the semiconductor substrate. An oxide layer is formed on the semiconductor substrate. A second ion implantation with the second type dopant is performed to form a second diffusion region within the first diffusion region. A silicon nitride layer is formed on the oxide layer, through which an opening penetrates to exposed the oxide layer. A third ion implantation with the second type dopant is performed using the silicon nitride layer as a mask to form a third diffusion region within the second diffusion region. Drive-in is performed to deepen the third diffusion region. The silicon nitride layer is removed. The exposed oxide layer is transformed into a field oxide layer.

Abstract: A method of fabricating a MOS device with a localized punchthrough stopper. In the process, a dummy layer is employed to define a well for implanting the localized punchthrough stopper. The dummy layer is preferably made of silicon nitride, which has a high etching selectivity with respect to the oxide material forming sidewall spacers of MOS devices. The localized punchthrough stopper is formed at the boundary of the lightly-doped regions and the channel by implanting impurities through the well resulting from the removal of a portion of the dummy layer adjacent to the gate structure.

Abstract: The method includes forming a buried oxide layer in a substrate. A pad oxide layer is then form on the substrate. A silicon nitride layer is pattered on the surface of the pad oxide. Then, a thick field oxide (FOX) is formed on the pad oxide layer. Sidewall spacers are formed on the side walls of the opening of the silicon nitride layer. Next, the FOX is etched. An ion implantation is performed for adjusting the threshold voltage and anti-punch-through implantation. Subsequently, a thin silicon oxynitride layer is deposited on the surface of the silicon nitride, spacers and the opening. A polysilicon gate is then formed in the opening. Then, Then, the silicon oxynitride layer, silicon nitride and the spacers are removed. Source and drain are next created. The pad oxide layer and the FOX are then removed. Then, the lightly doped drain (LDD) are formed. Self-aligned silicide (SALICIDE) layer, polycide layer are respectively formed on the substrate exposed by the gate, and on the gate.

Abstract: The present invention includes forming gate structures having a nitride cap on the substrate. An ion implantation is used to dope ions into the substrate to form the lightly doped drain (LDD) structures. An oxide layer is formed on the gate structures. Subsequently, the oxide layer is etched back to form oxide spacers on the side walls of the gate structures. Next, an ion implantation with a high dose is carried out to dope nitrogen ions into the oxide spacers, the cap silicon nitride and the silicon substrate. The cap silicon nitride layer is then removed. Then, a refractory or noble metal layer is sputtered on the substrate, nitride doped oxide spacers and the gates. A first step thermal process is performed to form SALICIDE and polycide. Next, an ion implantation is utilized to dope ions into the SALICIDE and polycide films. A second step thermal process is employed to form shallow source and drain junction.

Abstract: A gate conductor structure and method for forming the structure are provided whereby the overall gate length can be made with less susceptibility to lithography variations. The gate conductor is produced by defining a sidewall surface region and then forming the gate conductor material on that sidewall surface a closely controlled, defined lateral distance therefrom. The gate conductor length is therefore dependent primarily upon deposition technology rather than both deposition and lithography. Deposition can be controlled at the defined sidewall surface more closely than mask alignment, thin film development and etching processes of conventional designs. The gate conductor is formed from the sidewall surface such that the sidewall surface demonstrates a greater likelihood of forming a thicker sidewall spacer on one surface of the gate conductor than the opposing gate conductor surface.

Abstract: In a semiconductor device fabrication process, an active region of the semiconductor device is formed by doping an active region after formation of a relatively thick oxide layer. According to the process, a gate electrode is formed on a substrate and a relatively thick oxide layer is formed over the gate electrode. Portions of the relatively thick oxide layer are removed to expose a region of the substrate adjacent the gate electrode. The exposed region is then doped with a dopant to form an active region. The active region may form an LDD region. The relatively thick oxide layer may comprise a contact formation layer.

Abstract: In a semiconductor integrated circuit device having a high breakdown voltage CMOS transistor integrated for programming a programmable element, the present invention is intended to solve a problem of the drain breakdown voltage of the high breakdown voltage transistor going low as a result of a structure that the standard transistor and the high breakdown voltage transistor share common channel dope region. On a P-type monocrystal silicon substrate of 10-20 .OMEGA.cm specific resistivity having a P-well region and a silicon oxide film for separating the elements, a channel dope region for an insulated-gate type field effect transistor A and a channel dope region for an insulated-gate type field effect transistor B are formed separately, making the impurity concentration in one channel dope region two to ten times as high as that in the other channel dope region.

Abstract: A MOS transistor includes a semiconductor substrate of a first conductivity type having a major surface, a source and drain of a second conductivity type formed on the major surface to define a channel region therebetween, and a gate arranged in the channel region via an insulating film. The MOS transistor includes an impurity-implanted region of the first conductivity type located at a substrate portion which is deeper than the channel region and is shifted to a source side from a region corresponding to the channel region.

Abstract: An IGFET with source and drain contacts in close proximity to a gate with sloped sidewalls is disclosed. A method of making the IGFET includes forming a gate over a semiconductor substrate, wherein the gate includes a top surface, a bottom surface and opposing sidewalls, and the top surface has a substantially greater length than the bottom surface, forming a source and a drain that extend into the substrate, depositing a contact material over the gate, source and drain, and forming a gate contact on the gate, a source contact on the source, and a drain contact on the drain. The gate is separated from the source and drain contacts due to a retrograde slope of the gate sidewalls, and the gate contact is separated from the source and drain contacts due to a lack of step coverage in the contact material. Preferably, the contact material is a refractory metal, and the contacts are formed by converting the refractory metal into a silicide.

Abstract: A high-breakdown-voltage semiconductor device has a first offset layer and a second offset layer the dosage of which is higher than that of the first offset layer. When the gate is in the ON state, the first offset layer functions as a resurf layer. When the gate is in the OFF state, part of the charge in the first offset layer is neutralized by a drain current flowing through an element having a low ON-resistance, however, the second offset layer functions as a resurf layer. When the drain current is ?Acm.sup.-1 !, the amount of charge of electrons is q?C!, and the drift speed of carriers is .upsilon..sub.drift ?cms.sup.-1 !, the dosage n.sub.2 of the second offset layer is given by n.sub.2 .gtoreq.I.sub.D /(q.upsilon..sub.drift)?cms.sup.-2 !.

Abstract: A method is provided for increasing the electrical activation of dopants in a semiconductor device using rapid thermal processing (RTP). An aspect of the invention includes forming a gate on a semiconductor body (12), such as a substrate (14), and implanting a dopant (28) into the semiconductor body (12) proximate the gate. The dopant (28) is partially activated using a furnace. The dopant (28) is further activated using RTP. The activation of the dopant (28) through RTP in addition to the furnace annealing allows almost complete activation of the dopant while maintaining acceptable channel depths.

Abstract: A method of making an IGFET with a multilevel gate that includes upper and lower gate levels is disclosed. The method includes providing a semiconductor substrate with an active region, forming a gate insulator on the active region, forming a first gate material with a thickness of at most 1000 angstroms on the gate inslator and over the active region, forming a first photoresist layer over the first gate material, irradiating the first photoresist layer with a first image pattern and removing irradiated portions of the first photoresist layer to provide openings above the active region, etching the first gate material through the openings in the first photoresist layer using the first photoresist layer as an etch mask for a portion of the first gate material that forms a lower gate level, removing the first photoresist layer, forming an upper gate level on the lower gate level after removing the first photoresist layer, and forming a source and drain in the active region.

Abstract: The invention discloses method for fabricating a MOSFET on a substrate to improve device ruggedness.

Abstract: A method of forming a LDD fabrication by automatic phosphoric silicate glass (PSG) doping is disclosed herein. A phosphoric silicate glass serves as a diffusion source. The phosphorous ions of phosphoric silicate glass can be driven into a substrate to form a lightly-doped drain (LDD)by a high temperature during a thermal annealing process. The diffusion method can prevent from the damage in the substrate and the increasing of leakage current. Additionally, a thermal oxide layer is formed on the gate electrode and the surface of the substrate by the thermal oxidation process. The thermal oxide layer can prevent ions from sequentially diffusing into the substrate during the subsequent thermal treatment process. Therefore, the present invention can effectively control the impurity concentration of the lightly-doped drain (LDD) to prevent from the impurity concentration of the LDD over high.

Abstract: There is provided an active matrix type display in which thin film transistors having required characteristics are provided selectively in a pixel matrix portion and a peripheral driving circuit portion. In a structure having the pixel matrix portion and the peripheral driving circuit portion on the same substrate, N-channel type thin film transistors having source and drain regions formed through a non-self-alignment process and low concentrate impurity regions formed through a self-alignment process are formed in the pixel matrix portion and in an N-channel driver portion of the peripheral driving circuit portion. A P-channel type thin film transistor in which no low concentrate impurity region is formed and source and drain regions are formed only through the self-alignment process is formed in a P-channel driver portion of the peripheral driving circuit portion.

Abstract: A method for manufacturing a buried transistor, which includes the steps of forming a field oxide layer in a substrate, the field oxide region having a central portion having a greater thickness than opposite edge portions thereof, forming source/drain regions in the substrate, on opposite sides of the field oxide layer, removing the field oxide layer, and forming a gate electrode on the resultant structure.

Abstract: A method of fabricating a transistor. A dielectric layer is formed on an upper surface of a semiconductor substrate. A photoresist layer is then deposited on a dielectric layer and patterned with a photolithography exposure device to expose a region of the dielectric layer having a lateral dimension approximately equal to the minimum feature size resolvable by the photolithography exposure device. The exposed region of the dielectric layer is then removed to form a trench in the dielectric layer having opposed dielectric sidewalls and to expose a channel region of the semiconductor substrate having a lateral dimension approximately equal to the minimum feature size. First and second spacer structures are then formed on the respective dielectric sidewalls. The spacer structures shadow peripheral portions of the exposed channel region. A channel dielectric is then formed between the first and second spacer structures.

Abstract: The method includes the following steps: delimiting active areas on a substrate, forming gate electrodes insulated from the substrate on the active areas, and subjecting the front surface of the substrate to several implantation steps with doping ion beams to form source and drain regions with the use of the gate electrodes as masks. The direction of the implantation beam is defined by an angle of inclination to the front surface and by an orientation to a reference line on the front surface. To avoid performing numerous implantation steps without foregoing channels of uniform and constant length, the widths of the gate electrode strips are determined at the design stage in relation to the orientation of the strips to the reference line and on the orientation of the directions of the implant beams.