Abstract: A semiconductor device includes a semiconductor substrate, source and drain regions formed on the semiconductor substrate, a recess channel that is formed on the inner surface of a recess region, which is formed on the semiconductor substrate between the source and drain regions, and in an epitaxial semiconductor film in which dopants are doped. The semiconductor device further includes a gate insulating film formed on the recess channel, and a gate electrode that fills the recess region and is formed on the gate insulating film.

Abstract: A method according to some embodiments of the invention includes defining an active region by forming a trench device isolation region on an integrated substrate, forming a mask pattern that exposes a channel sub-region of the active region and the trench device isolation region adjacent to the channel sub-region, etching the trench device isolation region, which is exposed by the mask pattern, to be recessed to a first depth using the mask pattern as an etch mask, etching the channel sub-region to form a gate trench having a second depth that is deeper than the first depth using the mask pattern as an etch mask, and forming a recess gate that fills the gate trench.

Abstract: The semiconductor device according to the invention includes a substrate, a field insulating region which delimits an active region of the semiconductor substrate, a collector, at least one collector contact region associated with the collector, and a base with an associated base connection region. The collector and the collector contact region are formed in the same active region. In addition the base connection region extends partially over the active region and is separated from the surface of the active region by an insulator layer.

Abstract: A method for fabricating a semiconductor device with a metal-polycide gate and a recessed channel, including the steps of: forming trenches for a recessed channel in an active area of a semiconductor substrate; forming a gate insulating layer on the semiconductor substrate having the trenches; forming a gate conductive layer on the entire surface of the resulting structure so that the trenches are buried; forming a silicon-rich amorphous metal silicide layer and a gate hard mask on the gate conductive layer; etching the resulting structure until upper portions of the gate conductive layer are removed by a predetermined thickness, upon first patterning for gate stacks, and forming a metal layer on the entire surface of the resulting structure; forming lateral metal capping layers on sides of the silicon-rich amorphous metal silicide layer by blanket etching, completing formation of gate stacks; and thermally processing the silicon-rich amorphous metal silicide layer to form a crystallized metal silicide layer.

Abstract: A semiconductor device including a metal oxide layer, a channel area of the metal oxide layer, a preservation layer formed on the channel area of the metal oxide layer, and at least two channel contacts coupled to the channel area of the metal oxide layer, and a method of forming the same.

Abstract: An integrated circuit includes multiple layers. A semiconductor-on-insulator (SOI) wafer can be used to house transistors. Two substrates or wafers can be bonded to form the multiple layers. A strained semiconductor layer can be between a silicon germanium layer and a buried oxide layer. A hydrogen implant can provide a breaking interface to remove a silicon substrate from the silicon germanium layer.

Abstract: A method for fabricating a semiconductor device with a recessed channel, including the steps of: forming trenches for a recessed channel in an active area of a semiconductor substrate; forming a gate insulating layer on the semiconductor substrate having the trenches; forming a gate conductive layer on the entire surface of the resulting structure so that the trenches are buried; forming a silicon-rich amorphous metal silicide layer having seams on the gate conductive layer; filling the seams of the silicon-rich amorphous metal silicide layer with a metal thin film; forming a gate hard mask on the silicon-rich amorphous metal silicide layer and the metal thin film; patterning the gate insulating layer, the gate conductive layer, the silicon-rich amorphous metal silicide layer and the gate hard mask to form gate stacks; and thermally processing the silicon-rich amorphous metal silicide layer and the metal thin film to form a crystallized metal silicide layer.

Abstract: Memory elements including a first electrode and a second electrode. A chalcogenide material layer is between the first and second electrodes and a tin-chalcogenide layer is between the chalcogenide material layer and the second electrode. A selenide layer is between the tin-chalcogenide layer and the chalcogenide material layer. Optionally, a metal layer, for example a silver layer, is between the tin-chalcogenide layer and the second electrode. Methods for forming the memory elements are also provided.

Abstract: A metal-oxide-semiconductor (MOS) transistor device is provided. The MOS transistor device includes a substrate, a gate structure, a spacer, a source/drain region and a barrier layer. The gate structure is disposed on the substrate. The gate structure includes a gate and a gate dielectric layer disposed between the gate and the substrate. The spacer is disposed on the sidewall of the gate structure. The source/drain region is disposed in the substrate on two sides of the spacer. The barrier layer is disposed around the source/drain region. The source/drain region and the barrier layer are fabricated using an identical material. However, the doping concentration of the source/drain region is larger than the doping concentration of the barrier layer.

Abstract: An improved n-channel integrated lateral DMOS (10) in which a buried body region (30), beneath and self-aligned to the source (18) and normal body diffusions, provides a low impedance path for holes emitted at the drain region (16). This greatly reduces secondary electron generation, and accordingly reduces the gain of the parasitic PNP bipolar device. The reduced regeneration in turn raises the critical field value, and hence the safe operating area.

Abstract: In accordance with the present invention, a metal oxide semiconductor (MOS) transistor has a substrate of a first conductivity type. A drift region of a second conductivity type extends over the substrate. A body region of the first conductivity type is in the drift region. A source region of the second conductivity is in the body region. A gate extends over a surface portion of the body region. The surface portion of the body region extends between the source region and the drift region to form a channel region of the transistor. A drain region of the second conductivity type is in the drift region. The drain region is laterally spaced from the body region. A first buried layer of the second conductivity type is between the substrate and drift region. The first buried layer laterally extends from under the body region to under the drain region. A second buried layer of the first conductivity type is between the first buried layer and the drift region.

Abstract: A gate-all-around (GAA) transistor device has a pair of pillars that include the source/drain regions, a channel region bridging the source/drain regions, and a gate electrode and gate oxide which surround the channel region. The pillars are formed by providing a mono-crystalline silicon substrate, etching the substrate to form a pair of spaced-apart trenches such that a wall of the mono-crystalline silicon stands between the trenches, filling the trenches with insulative material, implanting impurities into the wall of mono-crystalline silicon, and forming an opening in the wall such that portions of the wall remain as pillars. A sacrificial layer is formed at the bottom of the opening. Then, the channel region is formed atop the sacrificial layer between the pillars. The sacrificial layer is subsequently removed and the gate oxide and gate electrode are formed around the channel region.

Abstract: The present invention comprises a method for forming an ultra-thin channel MOSFET and the ultra-thin channel MOSFET produced therefrom. Specifically, the method comprises providing an SOI substrate having a buried insulating layer underlying an SOI layer; forming a pad stack atop the SOI layer; forming a block mask having a channel via atop the pad stack; providing a localized oxide region in the SOI layer on top of the buried insulating layer thereby thinning a portion of the SOI layer, the localized oxide region being self-aligned with the channel via; forming a gate in the channel via; removing at least the block mask; and forming source/drain extensions in the SOI layer abutting the thinned portion of the SOI layer. Providing the localized oxide region further comprises implanting oxygen dopant through the channel via into a portion of the SOI layer; and annealing the dopant to create the localized oxide region.

Abstract: A multiple channel transistor provides a transistor with an improved drive current and speed by using tunable hot carrier effects. A thin gate oxide has a carrier confinement layer formed on top thereof. Holes produced by hot carrier effects are retained by the carrier confinement layer directly above the gate oxide layer. The holes switch on the bottom transistor of the multi-channel transistor, thereby increasing the drive current.

Abstract: The present invention relates to a non-volatile memory device having conductive sidewall spacers and a method for fabricating the same. The non-volatile memory device includes: a substrate; a gate insulation layer formed on the substrate; a gate structure formed on the gate insulation layer; a pair of sidewall spacers formed on sidewalls of the gate structure; a pair of conductive sidewall spacers for trapping/detrapping charges formed on the pair of sidewall spacers; a pair of lightly doped drain regions formed in the substrate disposed beneath the sidewalls of the gate structure; and a pair of source/drain regions formed in the substrate disposed beneath edge portions of the pair of conductive sidewall spacers.

Abstract: Drain-extended MOS transistors (T1, T2) and semiconductor devices (102) are described, as well as fabrication methods (202) therefor, in which a p-buried layer (130) is formed prior to formation of epitaxial silicon (106) over a substrate (104), and a drain-extended MOS transistor (T1, T2) is formed in the epitaxial silicon layer (106). The p-buried layer (130) may be formed above an n-buried layer (120) in the substrate (104) for high-side driver transistor (T2) applications, wherein the p-buried layer (130) extends between the drain-extended MOS transistor (T2) and the n-buried layer (120) to inhibit off-state breakdown between the source (154) and drain (156).

Abstract: A trench MIS device is formed in a semiconductor die that contains a P-epitaxial layer that overlies an N+ substrate and an N-epitaxial layer. In one embodiment, the device includes a drain-drift region that extends from the bottom of the trench to the N-epitaxial layer. A termination region of the die includes a half-trench at an edge of the die and an N-type region that extends from a bottom of the half-trench to the substrate. An insulating layer and an overlying metal layer extend from the surface of the epitaxial layer into the half-trench. Preferably, the elements of the termination region are formed during the same process steps that are used to form the active elements of the device.

Abstract: The present invention provides a semiconductor device that has reduced a short-channel effect by preventing the effective channel length at the sides of a channel of a transistor from decreasing by forming the length of a gate electrode to be different according to the parts. The semiconductor device according to the present invention includes a semiconductor substrate including active regions where a semiconductor device is to be fabricated and isolation regions for electrically isolating the active regions. A gate electrode is formed to go across the active region. A source and a drain are formed in the active region at both sides of the gate electrode, wherein the length of the gate electrode on the upper surface of the sides of the active region is longer than the length of the gate electrode of the center of the active region.

Abstract: Disclosed are a semiconductor devices and method of fabricating the same. Anti-etch films are formed in the top corners of the device isolation film using a material that has a different etch selectivity ratio from nitride or oxide and is not etched in an oxide gate pre-cleaning process. It is thus possible to prevent formation of a moat at the top corners of the device isolation film and the gate oxide film from being thinly formed, thereby improving reliability and electrical characteristics of the device.

Abstract: An integrated circuit device includes a gate electrode formed on an active region of an integrated circuit device and on a field isolation layer adjacent to the active region. A source region and a drain region are in the active region on alternate sides of the gate electrode. At least one buried insulation layer is beneath the drain region or the source region.

Abstract: An ESD protection device (20) comprises an N-type epitaxial collector (21), a first, lightly doped, deep base region (221) and second, highly doped, shallow base region (222) that extends a predetermined lateral dimension. The device responds to an ESD event by effecting vertical breakdown between the base regions and the N-type epitaxial collector. The ESD response is controlled by the predetermined lateral dimension, S, which, in one embodiment, may be is determined by a single masking step. Consequently, operation of the ESD protection device is rendered relatively insensitive to the tolerances of a fabrication process, and to variations between processes.

Abstract: A method for forming isolation layer in a vertical DRAM. A semiconductor substrate with a plurality of first trenches is provided, with a collar dielectric layer is formed on a sidewall of each, and each filled with a first conducting layer. A patterned mask layer is formed on the semiconductor substrate, and the semiconductor substrate is etched using the patterned mask layer as an etching mask to form a plurality of second trenches. The patterned mask layer is removed. Each second trench is filled with an insulating layer acting as an isolation. Each of first conducting layers is etched to form a plurality of grooves. A doped area acting as a buried strap is formed in the semiconductor substrate beside each groove. A trench top insulating layer is formed in the bottom surface of each trench. Each first trench is filled with a second conducting layer acting as a gate.

Abstract: Structures and methods for programmable memory address and decode circuits with low tunnel barrier interpoly insulators are provided. The decoder for a memory device includes a number of address lines and a number of output lines wherein the address lines and the output lines form an array. A number of logic cells are formed at the intersections of output lines and address lines. Each of the logic cells includes a floating gate transistor which includes a first source/drain region and a second source/drain region separated by a channel region in a substrate. A floating gate opposes the channel region and is separated therefrom by a gate oxide. A control gate opposing the floating gate. The control gate is separated from the floating gate by a low tunnel barrier intergate insulator. The low tunnel barrier intergate insulator includes a metal oxide insulator selected from the group consisting of PbO, Al2O3, Ta2O5, TiO2, ZrO2, Nb2O5 and/or a Perovskite oxide tunnel barrier.

Abstract: A structure for protecting a semiconductor circuit from electrostatic discharge is provided. The structure comprises a semiconductor substrate of a first conductivity type having two wells of a second conductivity type spaced laterally apart. The wells each comprise a first portion having a first concentration of an impurity of the second conductivity type and a second portion comprising source and drain regions having a second concentration of an impurity of the second conductivity type. The second concentration is greater than the first concentration. The wells are implanted in the substrate of a silicon-on-insulator semiconductor device. Conductive plugs extend through the silicon and insulator layers and make electrical contact with the wells, allowing the dissipation of excess current and heat into the semiconductor substrate.

Abstract: A method for manufacturing an integrated circuit structure includes providing a semiconductor substrate and forming at least one oxide-nitride-oxide dielectric layer above the semiconductor substrate. At least one implantation is formed into at least one area of the semiconductor substrate beneath the oxide-nitride-oxide dielectric layer subsequent to the formation of the oxide-nitride-oxide dielectric layer.

Abstract: A disclosed method for fabricating a structure in a semiconductor die comprises steps of implanting a deep N well in a substrate, depositing an epitaxial layer over the substrate, and forming a P well and a lateral isolation N well over the deep N well, wherein the lateral isolation N well and the P well are fabricated in the substrate and the epitaxial layer, and wherein the lateral isolation N well laterally surrounds the P well, and wherein the deep N well and the lateral isolation N well electrically isolate the P well. Implanting a deep N well can comprise steps of depositing a screen oxide layer over the substrate, forming a mask over the screen oxide layer, implanting the deep N well in the substrate, removing the mask, and removing the screen oxide layer. Depositing the epitaxial layer can comprise depositing a single crystal silicon over the substrate.

Abstract: A method of manufacturing a semiconductor device includes providing a semiconductor substrate having a heavily doped region of a first conductivity and has a lightly doped region of the first conductivity. The semiconductor substrate a plurality of trenches etched into an active region of the substrate forming a plurality of mesas. A preselected area in the active region is oxidized and then etched using a dry process oxide etch to remove the oxide in the bottoms of the trenches. A protective shield is formed over a region at a border between the active region and the termination region. The protective shield is partially removed from over the preselected area. Dopants are implanted at an angle into mesas in the preselected area. The plurality of trenches are with an insulating material, the top surface of the structure is planarized and a superjunction device is formed on the structure.

Abstract: A method for fabrication of a high-voltage, high-frequency MOS-transistor combines a deep n-well and a p-well process and the formation of an extended drain region (45), and a channel region (31), the channel having a short length and becoming well aligned with the gate edge. The deep n-well (11) and the p-well (19) are both produced by ion implantation. The method is compatible with a standard CMOS process and gives low manufacturing costs, increased breakdown voltage, better overall high-frequency performance, and the prevention of the “body effect” occurring by isolation of the p-well.

Abstract: A transistor structure fabricated on thin SOI is disclosed. The transistor on thin SOI has gated n+ and p+ junctions, which serve as switches turning on and off GIDL current on the surface of the junction. GIDL current will flow into the floating body and clamp its potential and can thus serve as an output node. The transistor can function as an inverter. The body (either n-well or p-well) is isolated from the n+ or P+ “GIDL switches” by a region of opposite doping type, i.e., p-base and n-base. The basic building blocks of logic circuits, e.g., NAND and NOR gates, are easily implemented with such transistors on thin SOI wafers. These new transistors on thin SOI only need contacts and metal line connections on the VCC and VSS. The connection of fan-outs (between the output and input) can be implemented by capacitor coupling. The transistor structure and operation is useful for high-performance, low-voltage, and low-power VLSI circuits on SOI wafers.

Abstract: A semiconductor device has a resin package layer on a principal surface of a semiconductor chip, on which a number of bump electrodes are formed, wherein the semiconductor device has a chamfer surface or a stepped surface on a top edge part such that the external shock or stress applied to such an edge part is dissipated by the chamfer surface of the stepped surface.

Abstract: A structure for use as a MOSFET employs an SOI wafer with a SiGe island resting on the SOI layer and extending between two blocks that serve as source and drain; epitaxially grown Si on the vertical surfaces of the SiGe forms the transistor channel. The lattice structure of the SiGe is arranged such that the epitaxial Si has little or no strain in the direction between the S and D and a significant strain perpendicular to that direction.

Abstract: The present invention relates to a method of forming a quantum wire gate device. The method includes patterning a first oxide upon a substrate. Preferably the first oxide pattern is precisely and uniformly spaced to maximize quantum wire numbers per unit area. The method continues by forming a first nitride spacer mask upon the first oxide and by forming a first oxide spacer mask upon the first nitride spacer mask. Thereafter, the method continues by forming a second nitride spacer mask upon the first oxide spacer mask and by forming a plurality of channels in the substrate that are aligned to the second nitride spacer mask. A dielectric is formed upon the channel length and the method continues by forming a gate layer over the plurality of channels. Because of the inventive method and the starting scale, each of the plurality of channels is narrower than the mean free path of semiconductive electron flow therein.

Abstract: A method of formation of a deep trench vertical transistor is provided. A deep trench with a sidewall in a doped semiconductor substrate is formed. The semiconductor substrate includes a counterdoped drain region in the surface thereof and a channel alongside the sidewall. The drain region has a top level and a bottom level. A counterdoped source region is formed in the substrate juxtaposed with the sidewall below the channel. A gate oxide layer is formed on the sidewalls of the trench juxtaposed with a gate conductor. Perform the step of recessing the gate conductor below the bottom level of the drain region followed by performing angled ion implantation at an angle ?+? with respect to vertical of a counterdopant into the channel below the source region and performing angled ion implantation at an angle ? with respect to vertical of a dopant into the channel below the source.

Abstract: A strained-channel transistor structure with lattice-mismatched zone and fabrication method thereof. The transistor structure includes a substrate having a strained channel region, comprising a first semiconductor material with a first natural lattice constant, in a surface, a gate dielectric layer overlying the strained channel region, a gate electrode overlying the gate dielectric layer, and a source region and drain region oppositely adjacent to the strained channel region, with one or both of the source region and drain region comprising a lattice-mismatched zone comprising a second semiconductor material with a second natural lattice constant different from the first natural lattice constant.

Abstract: In one example, a method of forming a transistor above a silicon-on-insulator substrate comprised of a bulk substrate, a buried oxide layer and an active layer, the bulk substrate being doped with a first type of dopant material is disclosed. The method comprises performing a first ion implant process using a dopant material that is of a type opposite the first type of dopant material to form a first well region within the bulk substrate, performing a second ion implant process using a dopant material that is the same type as the first type of dopant material to form a second well region in the bulk substrate within the first well, the transistor being formed in the active layer above the second well, forming a conductive contact to the first well and forming a conductive contact to the second well.

Abstract: A semiconductor arrangement including: a substrate having a substrate layer (13) with an upper and lower surface, the substrate layer (13) being of a first conductivity type; a first buried layer (12) in the substrate, extending along said lower surface below a first portion of said upper surface of said substrate layer (13), and a second buried layer (12) in the substrate, extending along said lower surface below a second portion of said upper surface of said substrate layer (13); a first diffusion (26) in said first portion of said substrate layer (13), being of a second conductivity type opposite to said first conductivity type and having a first distance to said first buried layer (12) for defining a first breakdown voltage between said first diffusion (26) and said first buried layer (12); a second diffusion (45) in said second portion of said substrate layer (13), being of said second conductivity type and having a second distance to said second buried layer (12) for defining a second breakdown volta

Abstract: A double gate electrode for a field effect transistor is fabricated by forming in a substrate, a trench and a tunnel that extends from a sidewall of the trench parallel to the substrate. An insulating coating is formed inside the tunnel. A bottom gate electrode is formed within the insulating coating inside the tunnel. An insulating layer is formed on the substrate and a top gate electrode is formed on the insulating layer opposite the bottom gate electrode.

Abstract: On the surface of a semiconductor material of a first conductivity type 101a, a lateral MOS transistor 100 is described surrounded by a well 171 of the opposite conductivity type and, nested within the well, an electrical isolation region 102. The semiconductor region 101a embedding this transistor has a resistivity higher than the remainder of the semiconductor material 101 and further contains a buried layer 160 of the opposite conductivity type. This layer 160 extends laterally to the wells 171, thereby electrically isolating the near-surface portion of the semiconductor region from the remainder of the semiconductor material, and enabling the MOS transistor to operate as an electrically isolated high-voltage I/O transistor for circuit noise reduction, while having low drain junction capacitance. In the first embodiment of the invention (FIG.

Abstract: The thin film transistor formed of polycrystalline silicon is positioned adjacent a heat reaction chamber. The gate electrode for the transistor is formed within a silicon substrate and a gate dielectric is positioned over the gate electrode. A pass transistor is coupled to the gate electrode, the pass transistor having a source/drain region in the same semiconductor substrate and positioned adjacent to the gate electrode of the thin film heating transistor. When the pass transistor is enabled, a voltage is applied to the gate electrode which causes the current to flow from the drain to the source of the thin film transistor. The current flow passes through a highly resistive region which generates heat that is transmitted to the heat reaction chamber.

Abstract: A semiconductor substrate includes a first principal plane and a second principal plane opposite this first principal plane. A first semiconductor region is formed on the first principal plane of the semiconductor substrate. Second and third semiconductor regions are formed separately from each other on the first semiconductor region. A gate electrode is formed, via a gate insulator, on the first semiconductor region between the second semiconductor region and the third semiconductor region. An electric conductor is formed up to the semiconductor substrate from the second semiconductor region and electrically connects the second semiconductor region with the semiconductor substrate. A first main electrode is formed on the second principal plane of the semiconductor substrate and is electrically connected to the semiconductor substrate. A second main electrode is formed on the first semiconductor region via insulators and is electrically connected to the third semiconductor region.

Abstract: A fin field effect transistor includes a fin, a source region, a drain region, a first gate electrode and a second gate electrode. The fin includes a channel. The source region is formed adjacent a first end of the fin and the drain region is formed adjacent a second end of the fin. The first gate electrode includes a first layer of metal material formed adjacent the fin. The second gate electrode includes a second layer of metal material formed adjacent the first layer. The first layer of metal material has a different work function than the second layer of metal material. The second layer of metal material selectively diffuses into the first layer of metal material via metal interdiffusion.

Abstract: A method and apparatus to form a high-concentration, indium-fluorine retrograde well within a substrate. The indium-fluorine retrograde well includes an indium concentration greater than about 3E18/cm3.

Abstract: A buried gate electrode of a buried MOS transistor formed within a trench in an active region wherein a gate oxide film and a gate electrode are buried in the trench, and a lower electrode of a PIP capacitor formed on a device isolation, are simultaneously formed by etching of polycrystalline silicon formed on an entire surface of the structure.

Abstract: A semiconductor device has a structure in which an impurity diffusion region with an impurity concentration lower than an impurity concentration of a source and a drain is formed between the source and drain and a channel below the gate, having an asymmetric shape with respect to a center line along which the gate extends.

Abstract: An improved method for forming a flash memory is disclosed. A self-aligned source implanted pocket located underneath and around the source line junction is formed after the field oxide between adjacent word lines is removed, and before or after the self-aligned source doping is carried out, so that the configuration of the implanted boron follows the source junction profile.

Abstract: A semiconductor device includes an elongated, blade-shaped semiconductor element isolated from a surrounding region of a semiconductor substrate by buried and side oxide layers. A polysilicon post disposed at one end of the element has a bottom portion extending through the buried oxide to contact the substrate, providing for electrical and thermal coupling between the element and the substrate and for gettering impurities during processing. A device fabrication process employs a selective silicon-on-insulator (SOI) technique including forming trenches in the substrate; passivating the upper portion of the element; and performing a long oxidation to create the buried oxide layer. A second oxidation is used to create an insulating oxide layer on the sidewalls of the semiconductor element, and polysilicon material is used to fill the trenches and to create the post.

Abstract: The invention concerns a semi-conductor device comprising on a substrate: a first dynamic threshold voltage MOS transistor (10), with a gate (116), and a channel (111) of a first conductivity type, and a current limiter means (20) connected between the gate and the channel of said first transistor. In accordance with the invention, this first transistor is fitted with a first doped zone (160) of the first conductivity type, connected to the channel, and the current limiter means comprises a second doped zone (124) of a second conductivity type, placed against the first doped zone and electrically connected to the first zone by an ohmic connection. Application to the manufacture of CMOS circuits.

Abstract: A buried bit line and a fabrication method thereof, wherein the device includes a substrate, a shallow doped region disposed in the substrate, a deep doped region disposed in the substrate below a part of the shallow doped region, wherein the shallow doped region and the deep dope region together form a bit line of the memory device.

Abstract: The present invention relates to a method for fabricating a metal-oxide semiconductor (MOS) transistor having a gate electrode with a stack structure of a polysilicon layer, a tungsten nitride barrier layer and a tungsten layer. According to the present invention, a depth from a lastly deposited nitride layer to a bottom surface of a trench is shallower, and thereby decreasing incidences of a void generation. Also, the present invention provides an advantage of an elaborate manipulation of well and channel dopings by performing ion-implantations with two different approaches. Furthermore, it is possible to enhance device characteristics by decreasing gate induced drain leakage (GIDL) currents and improving a capability of driving currents. This decrease of the GIDL currents and the improved driving current capability are obtained by forming the gate oxide layer with different thicknesses.

Abstract: A semiconductor device and a method for forming the same are disclosed. The semiconductor device includes an epitaxial source/drain junction layer having an insulating film thereunder. The method comprises the step of forming a under-cut under an epitaxial source/drain junction layer so that an insulating film filling the under-cut can be formed.