Abstract: A semiconductor device includes a semiconductor substrate including an active region and a gate region, and a gate channel formed in a portion of the active region that overlaps the gate region. The gate channel includes a recessed multi-bulb structure.

Abstract: Example embodiments relate to a non-volatile semiconductor memory device and a method of manufacturing the same. A semiconductor device includes an isolation layer protruding from a substrate, a spacer, a tunnel insulation layer, a floating gate, a dielectric layer pattern and a control gate. The spacer may be formed on a sidewall of a protruding portion of the isolation layer. The tunnel insulation layer may be formed on the substrate between adjacent isolation layers. The floating gate may be formed on the tunnel insulation layer. The floating gate contacts the spacer and has a width that gradually increases from a lower portion toward an upper portion. The dielectric layer pattern and the control gate may be sequentially formed on the floating gate.

Abstract: A method of manufacturing a semiconductor apparatus includes forming a trench in a semiconductor layer, forming a gate electrode inside the trench, forming a thermally-oxidized film on the gate electrode inside the trench, forming a silicate glass film on the thermally-oxidized film inside the trench, forming a body region inside the semiconductor layer, and forming a source region on the body region. The method provides a semiconductor apparatus having reduced fluctuation of a channel length and low ON-resistance.

Abstract: According to some embodiments of the invention, a method of forming a transistor includes forming a device isolation layer in a semiconductor substrate. The device isolation layer is formed to define at least one active region. A channel region is formed in a predetermined portion of the active region of the semiconductor substrate. Two channel portion holes are formed to extend downward from a main surface of the semiconductor substrate to be in contact with the channel region. Gate patterns fill the channel portion holes and cross the active region. The resulting transistor is capable of ensuring a constant threshold voltage without being affected by an alignment state of the channel portion hole and the gate pattern.

Abstract: A semiconductor device includes an active region including a surface region and a first recess formed below the surface region, the active region extending along a first direction; a device isolation structure provided on an edge of the active region; a gate line traversing over the surface region of the active region along a second direction orthogonal to the first direction; a second recess formed in the device isolation structure to receive a given portion of the gate line into the second recess; a first junction region formed in the active region beneath the first recess and on a first side of the gate line; and a second junction region formed on a second side of the gate line and above the first junction region, wherein the first and second junction regions define a vertical-type channel that extends along lateral and vertical directions.

Abstract: A method of manufacturing a semiconductor device having buried gates may include forming a stacked structure of sequentially stacked first mask patterns and second mask patterns with equal widths to expose active regions and isolation regions of a semiconductor substrate. After forming reduced first mask patterns by decreasing the width only of the first mask patterns, trenches may be formed in the active regions and the isolation regions by etching the exposed portions of the semiconductor substrate using the second mask patterns as an etch mask. Then, gate insulating films may be formed on inner walls of the trenches in the active regions, and a conductive material may be buried into the trenches in the active regions and the isolation regions to form gates.

Abstract: Disclosed are an asymmetric recessed gate MOSFET, and a method for manufacturing the same. The asymmetric recessed gate MOSFET comprises: recess regions formed at a predetermined depth in a semiconductor; recessed gate electrodes formed at a predetermined height on a semiconductor substrate by gap-filling the recess regions, and misaligned with the recess region corresponding to one of the source/drain regions; spacers formed on sides of the recessed gate electrodes; and source/drain regions implanted with a dopant formed in the semiconductor substrate exposed between the spacers. The overlap between the gate electrodes and the source/drain regions can be reduced by having one of the source/drain regions misaligned with the recess regions in the recessed gate structure, and abnormal leakage current caused by consistency between an electron field max point A and a stress max pint B can be sharply reduced by changing the profile of the source/drain regions.

Abstract: The semiconductor device includes a device isolation structure formed in a semiconductor substrate to define an active region, a bridge type channel structure formed in the active region, and a coaxial type gate electrode surrounding the bridge type channel structure of a gate region. The bridge type channel structure is separated from the semiconductor substrate thereunder by a predetermined distance in a vertical direction.

Abstract: A semiconductor device, having a recessed gate and asymmetric dopant regions, comprises a semiconductor substrate having a trench with a first sidewall and a second sidewall, the heights of which are different from each other, a gate insulating layer pattern disposed on the semiconductor substrate, a gate stack disposed on the semiconductor such that the gate stack protrudes from the surface of the semiconductor substrate while the gate stack fills the trench, and first and second dopant regions disposed at the upper part of the semiconductor substrate adjacent to the first and second sidewalls of the trench, respectively, such that the first and second dopant regions have different steps.

Abstract: For fabricating multiple field effect transistors (FETs), a first conductive layer is deposited over first and second active regions of a semiconductor substrate. The first conductive layer is patterned over the second active region to form mold structures. Mask structures are formed between the mold structures. The second active region is patterned using the mask structures or using spacers formed at sidewalls of the mold structures to form multiple fins of a field effect transistor of a fin type. The first conductive layer is patterned over the first active region to form a gate of another field effect transistor of a different type.

Abstract: Disclosed herein is a transistor for a semiconductor device and a method of forming the same. According to the present invention, a novel transistor structure combining a plane channel transistor and a fin-type channel transistor formed on the semiconductor substrate is provided to secure a sufficient channel width as compared to that of the plane channel transistor, thereby satisfying drive current regulated for the transistor.

Abstract: A method for fabricating a semiconductor device includes: providing a substrate structure in which a plurality of gate lines are already formed; forming a capping layer over the substrate structure; oxidizing the capping layer; and forming an insulation layer over the oxidized capping layer. The capping layer may include a nitride-based material. The insulation layer may include substantially the same material as the capping layer. The oxidizing of the capping layer may comprise performing a radical oxidation process.

Abstract: A semiconductor device having a recessed active edge is provided. The semiconductor devices include an isolation layer disposed in a substrate to define an active region. A gate electrode is disposed to cross over the active region. A source region and a drain region are disposed in the active region on both sides of the gate electrode. A recessed region is disposed under the gate electrode and on an edge of the active region adjacent to the isolation layer. A bottom of the recessed region may be sloped down toward the isolation layer. The gate electrode may further extend into and fill the recessed region. That is, a gate extension may be disposed in the recessed region. A method of fabricating the semiconductor device is also provided.

Abstract: A method of fabricating a non-volatile memory device, wherein a gate insulating layer, a first conductive layer, a tunneling layer, a trap nitride layer, a blocking oxide layer, and a capping layer are sequentially formed over a semiconductor substrate of a peripheral region. A contact region of the capping layer is etched. A spacer is formed on sidewalls of the capping layer. A contact region of the blocking oxide layer is etched by using the spacer as a mask. The spacer is removed while etching a contact region of the trap nitride layer. A contact region of the tunneling layer is etched.

Abstract: A dual polysilicon gate of a semiconductor device includes a substrate having a first region, a second region, and a third region, a channel region with a recessed structure formed in the first region of the substrate, a gate insulating layer formed over the substrate, a first polysilicon layer filled into the channel region, and formed over the gate insulating layer of the first and second regions, a second polysilicon layer formed over the gate insulating layer of the third region, and an insulating layer doped with an impurity, and disposed inside the first polysilicon layer in the channel region.

Abstract: A method of manufacturing a local recess channel transistor in a semiconductor device. A hard mask layer is formed on a semiconductor substrate that exposes a portion of the substrate. The exposed portion of the substrate is etched using the hard mask layer as an etch mask to form a recess trench. A trench spacer is formed on the substrate along a portion of sidewalls of the recess trench. The substrate along a lower portion of the recess trench is exposed after the trench spacer is formed. The exposed portion of the substrate along the lower portion of the recess trench is doped with a channel impurity to form a local channel impurity doped region surrounding the lower portion of the recess trench. A portion of the local channel impurity doped region surrounding the lower portion of the recess trench is doped with a Vth adjusting impurity to form a Vth adjusting impurity doped region inside the local channel impurity doped region. The width of the lower portion of the recess trench is expanded.

Abstract: A method of manufacturing a semiconductor device is provided. Device separation portions defining first, second and third regions are formed in a substrate. A recess is formed at the first region. An N-type well is formed at the third region. An N-type polysilicon layer is formed at the first and second regions. A P-type polysilicon layer is formed at the third region. At least one of metal silicide film and a metal film is formed on the N-type polysilicon layer and the P-type polysilicon layer. Etching is performed to form a gate electrode including the N-type polysilicon layer at the first and second regions and a gate electrode including the P-type polysilicon layer at the third region. A cell transistor having a recess channel structure is formed at the first region, an nMOSFET structure is formed at the second region, and a pMOSFET structure is formed at the third region.

Abstract: A multi-step gate structure comprises a semiconductor substrate having a multi-step structure, a gate oxide layer positioned on the multi-step structure and a conductive layer positioned on the gate oxide layer. Preferably, the gate oxide layer has different thicknesses on each step surface of the multi-step structure. In addition, the multi-step gate structure further comprises a plurality of doped regions positioned in the semiconductor substrate under the multi-step structure. The channel length of the multi-step gate structure is the summation of the lateral width and the vertical depth of the multi-step gate structure, which is dramatically increased such that problems originated from the short channel effect can be effectively solved. Further, the plurality of doped regions under the multi-step structure are prepared by implanting processes having different dosages and dopants, which can control the thickness of the gate oxide layer and the threshold voltage of the multi-step gate structure.

Abstract: The semiconductor device having a recess channel transistor includes a device isolation structure formed in a semiconductor substrate to define an active region having a recess region at a lower part of sidewalls thereof and a recess channel region formed in the semiconductor substrate under the active region. A method for fabricating the semiconductor device includes forming a device isolation structure in a semiconductor substrate to form an active region having a recess region at a lower part of sidewalls thereof, a gate insulating film formed over the semiconductor substrate including the recess channel region, and a gate electrode formed over the gate insulating film to fill up the recess channel region.

Abstract: In accordance with an embodiment of the present invention, a gate structure for a U-shape Metal-Oxide-Semiconductor (UMOS) device includes a dielectric layer formed into a U-shape having side walls and a floor to form a trench surrounding a dielectric layer interior region, a doped poly-silicon layer deposited adjacent to the dielectric layer within the dielectric layer interior region where the doped poly-silicon layer has side walls and a floor surrounding a doped poly-silicon layer interior region, a first metal layer deposited on the doped poly-silicon layer on a side opposite from the dielectric layer where the first metal layer has side walls and a floor surrounding a first metal layer interior region, and an undoped poly-silicon layer deposited to fill the first metal layer interior region.

Abstract: Methods of manufacturing a semiconductor device having an RCAT are provided. The method includes forming a first recess having a first depth formed in an active region of a semiconductor substrate, and a second recess having a second depth that is less than the first depth formed in an isolation layer. The depth of the second recess is decreased by removing the isolation layer from the upper surface of the isolation layer by a desired thickness. A gate dielectric layer is formed on an inner wall of the first recess and a gate is formed on the gate dielectric layer.

Abstract: A recessed gate electrode structure includes a first recess and a second recess in communication with the first recess both formed in a substrate. The second recess is larger than the first recess. A gate dielectric layer is formed on a top surface of the substrate and on an inner surface of the first and second recesses. A first polysilicon layer fills the first recess and is doped with impurities at a first impurity density. A second polysilicon layer fills the second recess and is doped with the impurities at a second impurity density. A void is defined within the second polysilicon layer. A third polysilicon layer is formed on the gate dielectric and first polysilicon layers and is doped with the impurities at a third impurity density. Due to impurities in the second polysilicon layer, migration of the void within the second recess may be substantially prevented.

Abstract: A MOS transistor made in monolithic form, vias contacting the gate and the source and drain regions of the transistor being formed on the other side of the channel region with respect to the gate.

Abstract: A PMOS transistor and a method for fabricating a PMOS transistor. The method may include providing a semiconductor wafer having a PMOS transistor gate stack, source/drain extension regions, and active regions. The method may also include forming epi sidewalls, performing a ex-situ recess etch, and performing an in-situ recess etch. The ex-situ recess etch and the in-situ recess etch form recessed active regions. The PMOS transistor is formed by a method using ex-situ and in-situ etch and has epitaxial SiGe regions with a greatest width at the surface of the semiconductor wafer.

Abstract: A method of fabricating a semiconductor device having a recess channel structure is provided. A first recess is formed in a substrate. A liner and a filling layer are formed in the first recess. A portion of the substrate adjacent to the first recess and a portion of the liner and the filling layer are removed to form trenches. An insulation layer fills the trenches to form isolation structures. The filling layer is removed, using the liner as an etching stop layer, to expose the insulation layer. A portion of the exposed insulation layer is removed to form a second recess having divots adjacent to the sidewalls of the substrate. The liner is removed. A dielectric layer and a gate are formed over the substrate covering the second recess. Source and drain regions are formed in the substrate adjacent to the second recess.

Abstract: A semiconductor device having a recessed channel and a method for manufacturing the same. The semiconductor device comprises a semiconductor substrate formed with an isolation layer defining an active region including a channel region and a junction region, a recessed trench including a top trench formed within the channel region of the semiconductor substrate and a bottom trench formed from a bottom surface of the top trench with a width narrower than the top trench, and a gate stack overlapping the recessed trench and extending across the active region.

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: According to some embodiments of the invention, a method of forming a transistor includes forming a device isolation layer in a semiconductor substrate. The device isolation layer is formed to define at least one active region. A channel region is formed in a predetermined portion of the active region of the semiconductor substrate. Two channel portion holes are formed to extend downward from a main surface of the semiconductor substrate to be in contact with the channel region. Gate patterns fill the channel portion holes and cross the active region. The resulting transistor is capable of ensuring a constant threshold voltage without being affected by an alignment state of the channel portion hole and the gate pattern.

Abstract: A method of manufacturing a metal oxide semiconductor transistor having a metal gate is provided. The method firstly includes a step of providing a substrate. A dummy gate is formed on the substrate, a spacer is formed around the dummy gate, and doped regions are formed in the substrate outside of the dummy gate. A bevel edge is formed on the spacer, and a trench is formed in the inner sidewall of the spacer. A barrier layer, and a metal gate are formed in the trench and on the bevel edge, and the barrier layer will not form poor step coverage.

Abstract: A method for fabricating a semiconductor device with a step gated asymmetric recess is provided.

Abstract: A system and method is disclosed that prevents the formation of a vertical bird's beak structure in the manufacture of a semiconductor device. A polysilicon filled trench is formed in a substrate of the semiconductor device. One or more composite layers are then applied over the trench and the substrate. A mask and etch process is then applied to etch the composite layers adjacent to the polysilicon filled trench. A field oxide process is applied to form field oxide portions in the substrate adjacent to the trench. Because no field oxide is placed over the trench there is no formation of a vertical bird's beak structure. A gate oxide layer is applied and a protection cap is formed over the polysilicon filled trench to protect the trench from unwanted effects of subsequent processing steps.

Abstract: A semiconductor structure includes a semiconductor layer that includes an inverted V shaped channel region that allows avoidance of a raised source/drain region within the semiconductor structure. In one embodiment, a generally conventional gate electrode is located over a planar surface of the semiconductor layer over the inverted V shaped channel region. In another embodiment, the foregoing generally conventional gate electrode is used in conjunction with an inverted V shaped gate electrode that is located within an inverted V shaped notch that comprises the inverted V shaped channel region.

Abstract: The invention is intended to present an insulated gate type semiconductor device that can be manufactured easily and its manufacturing method while realizing both higher withstand voltage design and lower on-resistance design. The semiconductor device comprises N+ source region 31, N+ drain region 11, P? body region 41, and N? drift region 12. By excavating part of the upper side of the semiconductor device, a gate trench 21 is formed. The gate trench 21 incorporates the gate electrode 22. A P floating region 51 is provided beneath the gate trench 21. A further trench 35 differing in depth from the gate trench 21 may be formed, a P floating region 54 being provided beneath the trench 25.

Abstract: A method of manufacturing a semiconductor device, including: preparing a semiconductor substrate having an element-isolating film filled in the first trench and an active region; forming a mask-forming film over the semiconductor substrate; forming a first mask having an opening traversing the active region; performing anisotropic etching using the first mask to form a second mask made of the mask-forming film and a second trench having opposite exposed surfaces of the element-isolating film, being shallower than the first trench and being formed in the active region; implanting oxygen ions obliquely using the second mask such that oxygen ions are radiated at a region including a boundary between a surface of the semiconductor substrate inside the second trench and one of the opposite exposed surfaces of the element-isolating film; oxidizing the oxygen ion-implanted region inside the second trench to form an oxidized region; and removing the oxidized region.

Abstract: Methods for forming non-volatile memory cells include: (a) providing a semiconductor substrate having at least two source/drain regions, and a dielectric material disposed on the substrate above at least one of the at least two source/drain regions wherein the dielectric material has an exposed surface, and wherein the at least two source/drain regions are separated by a recess trench having an exposed surface, wherein the trench extends downward into the substrate to a depth position below the at least two source/drain regions; (b) forming a charge-trapping layer on the exposed surfaces of the dielectric material and the recess trench; and (c) forming a gate above the charge-trapping layer.

Abstract: A transistor including an active region and methods thereof. The active region may include corners with at least one of a rectangular, curved or rounded shape. The methods may include isotropically etching at least a portion of the active region such that the portion includes a desired shape.

Abstract: The semiconductor device includes an active region, a recess, a Fin-type channel region, a gate insulating film, and a gate electrode. The active region is defined by a device isolation structure formed in a semiconductor substrate. The recess is formed by etching the active region and its neighboring device isolation structure using an island-type recess gate mask as an etching mask. The Fin-type channel region is formed on the semiconductor substrate at a lower part of the recess. The gate insulating film is formed over the active region including the Fin-type channel region and the recess. The gate electrode is formed over the gate insulating film to fill up the Fin-type channel region and the recess.

Abstract: A semiconductor device includes a second-conductivity-type base region provided on a first-conductivity-type semiconductor layer, a first-conductivity-type source region provided on the second-conductivity-type base region, a gate insulating film covering an inner wall of a trench which passes through the second-conductivity-type base region and reaching the first-conductivity-type semiconductor layer, a gate electrode buried in the trench via the gate insulating film, and a second-conductivity-type region being adjacent to the second-conductivity-type base region below the first-conductivity-type source region, spaced from the gate insulating film, and having a higher impurity concentration than the second-conductivity-type base region.

Abstract: A semiconductor device and a method of manufacturing the same can satisfy a design rule reduction in a peripheral region. The semiconductor device includes a silicon substrate having an activation region formed by recessing a center portion of the silicon substrate lengthwise. A device isolation layer is formed on the silicon substrate for restricting the activation region. A gate is formed on the recessed activation region and has a smaller length than that of the recess, a source/drain extension region formed on a surface of the recessed activation region having no gate, spacers formed on both sidewalls of the gate, and a source/drain region formed on a surface of the activation region including the spacers at both sides of the gate.

Abstract: A method of fabricating a transistor with a recessed channel is provided. The method includes forming trenches for a recessed channel on a semiconductor substrate, depositing an isolation layer on the semiconductor substrate on which the trenches are formed, depositing a gate dielectric layer on the semiconductor substrate so that the gate dielectric layer can be extended to bottoms and sidewalls of the trenches, forming gates to fill the trenches, and forming source and drain regions in the semiconductor substrate adjacent to the gates.

Abstract: A FET includes a trench in a semiconductor region. The trench has a lower portion with a shield electrode therein, and an upper portion with a gate electrode therein, where the upper portion is wider than the lower portion. The semiconductor region includes a substrate of a first conductivity type and a first silicon region of a second conductivity type over the substrate. The first silicon region has a first portion extending to a depth intermediate top and bottom surfaces of the gate electrode. The first silicon region has a second portion extending to a depth intermediate top and bottom surfaces of the shield electrode. The semiconductor region further includes a second silicon region of the first conductivity type between the lower trench portion and the second portion of the first silicon region that has a laterally-graded doping concentration decreasing in a direction away from the sidewalls of the lower trench portion.

Abstract: The invention is related to a MOS transistor and its fabrication method to reduce short-channel effects. Existing process has the problem of high complexity and high cost to reduce short-channel effects by using epitaxial technique to produce an elevated source and drain structure. In the invention, the MOS transistor, fabricated on a silicon substrate after an isolation module is finished, includes a gate stack, a gate sidewall spacer, and source and drain areas. The silicon substrate has a groove and the gate stack is formed in the groove.

Abstract: The invention includes methods for utilizing partial silicon-on-insulator (SOI) technology in combination with fin field effect transistor (finFET) technology to form transistors particularly suitable for utilization in dynamic random access memory (DRAM) arrays. The invention also includes DRAM arrays having low rates of refresh. Additionally, the invention includes semiconductor constructions containing transistors with horizontally-opposing source/drain regions and channel regions between the source/drain regions. The transistors can include gates that encircle at least three-fourths of at least portions of the channel regions, and in some aspects can include gates that encircle substantially an entirety of at least portions of the channel regions.

Abstract: A varying-width recess gate structure having a varying-width recess formed in a semiconductor device can sufficiently increase the channel length of the transistor having a gate formed in the varying-width recess, thereby effectively reducing the current leakage and improving the refresh characteristics. In the method of manufacturing the recess gate structure, etching is performed twice or more, so as to form a gate recess having varying width in the substrate, and a gate is formed in the gate recess.

Abstract: According to some embodiments of the invention, transistors of a semiconductor device have a punchthrough protection layer, and methods of forming the same are provided. A channel-portion hole extends downward from a main surface of a semiconductor substrate. A punchthrough protection layer and a channel-portion layer are sequentially formed at a lower portion of the channel-portion hole. A word line pattern fills an upper portion of the channel-portion hole, and is formed on the semiconductor substrate. The word line pattern is formed to have a word line and a word line capping layer pattern stacked thereon, and the channel-portion layer is a channel region. The punchthrough protection layer can reduce a leakage current of a capacitor of the transistor embodied in a DRAM.

Abstract: An insulated gate semiconductor device, specifically, a trench lateral MOSFET having improved hot carrier resistance can be provided without increasing the number of processes and device pitch and without degrading device breakdown voltages and on-resistance characteristics RonA. A junction depth Xj of a p base region of a TLPM (trench lateral power MOSFET) is made smaller than the depth of a trench, and the trench is formed with a depth Dt of about 1.2 ?m such that the junction does not contact a curved corner part at the bottom of the trench.

Abstract: The invention includes methods of forming recessed access devices. A substrate is provided to have recessed access device trenches therein. A pair of the recessed access device trenches are adjacent one another. Electrically conductive material is formed within the recessed access device trenches, and source/drain regions are formed proximate the electrically conductive material. The electrically conductive material and source/drain regions together are incorporated into a pair of adjacent recessed access devices. After the recessed access device trenches are formed within the substrate, an isolation region trench is formed between the adjacent recessed access devices and filled with electrically insulative material to form a trenched isolation region.

Abstract: An inner spacer is formed in a sidewall of a gate in contact with a first active region that is electrically connected to an upper capacitor, thereby reducing a gate induced drain leakage (GIDL). A structure of a recess gate transistor includes a gate insulation layer, a gate electrode, a first gate spacer, a second gate spacer and source/drain regions. The gate insulation layer is formed within a recess. The gate electrode is surrounded by the gate insulation layer and is extended from within the recess. The first gate spacer is spaced with a predetermined distance horizontally with a portion of the gate insulation layer, being formed in a sidewall of the gate electrode. The second gate spacer is formed in another part of the sidewall of the gate electrode. The source/drain regions are formed mutually oppositely on first and second active regions with the gate electrode therebetween.

Abstract: A MOS (metal oxide semiconductor) transistor with a trench-type gate is fabricated with a channel stopping region for forming an asymmetric channel region for reducing short channel effects. For example in fabricating an N-channel MOS transistor, a gate structure is formed within a trench that is within a P-well. A channel stopping region with a P-type dopant is formed to a first side of the trench to completely contain an N-type source junction therein. An N-type drain junction is formed within a LDD region to a second side of the trench, thus forming the asymmetric channel region.

Abstract: A metal oxide semiconductor (MOS) transistor having a recessed gate electrode and a fabrication method thereof are provided. The MOS transistor includes a semiconductor substrate and an isolation layer formed in a predetermined region of the semiconductor substrate to define an active region. A channel trench region is disposed within the active region to cross the active region. A gate insulating layer is disposed to cover sidewalls and a bottom of the channel trench region. The MOS transistor has a gate pattern that fills the channel trench region and crosses above the active region. A portion of the sidewall of the gate pattern is recessed at an upper corner of the channel trench region and has a width smaller than the width of the top of the gate pattern and smaller than the width of the channel trench region.