Abstract: First and second isolation trenches are formed into semiconductive material of a semiconductor substrate. The first isolation trench has a narrowest outermost cross sectional dimension which is less than that of the second isolation trench. An insulative layer is deposited to within the first and second isolation trenches effective to fill remaining volume of the first isolation trench within the semiconductive material but not that of the second isolation trench within the semiconductive material. The insulative layer comprises silicon dioxide deposited from flowing TEOS to the first and second isolation trenches. A spin-on-dielectric is deposited over the silicon dioxide deposited from flowing the TEOS within the second isolation trench within the semiconductive material, but not within the first isolation trench within the semiconductive material. The spin-on-dielectric is deposited effective to fill remaining volume of the second isolation trench within the semiconductive material.

Abstract: In a method of forming an isolation layer, first and second trenches are formed on a substrate. The first and the second trenches have first and second widths, respectively, and the second width is greater than the first width. A second isolation layer pattern partially fills the second trench. A first isolation layer pattern and the third isolation layer pattern are formed. The first isolation layer pattern fills the first trench, and the third isolation layer pattern is formed on the second isolation layer pattern and fills a remaining portion of the second trench.

Abstract: A self-alignment method for a recess channel dynamic random access memory includes providing a substrate with a target layer, a barrier layer and a lining layer, wherein the target layer has shallow trench isolation structures; patternizing the lining layer, barrier layer and target layer to form recess trench channels; depositing a dielectric layer onto the recess trench channel; forming an ion doped region in the target layer; removing a portion of the dielectric layer to expose a portion of the recess trench channel; forming a filler layer covered onto the recess trench channel; removing a portion of the filler layer to expose a portion of the recess trench channel; forming a passivation layer onto the recess trench channel; removing the passivation layer on the lining layer; and removing the lining layer to form a plurality of structural monomers disposed at the recess trench channel and protruded from the target layer.

Abstract: A semiconductor device includes: a first well and a second well formed in a substrate and having a different impurity doping concentration; a first isolation layer and a second isolation layer formed in the first well and the second well, respectively, and having a different depth; and a third isolation layer formed in a boundary region in which the first well and the second well are in contact with each other, and having a combination type of the first isolation layer and the second isolation layer.

Abstract: A semiconductor device includes: a semiconductor substrate having first and second areas; an STI isolation region being made of an isolation trench formed in the semiconductor substrate and an insulating film burying the isolation trench and defining a plurality of active regions in the first and second areas; a first structure formed on an area from the active region in the first area to a nearby STI isolation region and having a first height; and a second structure formed on an area from the active region in the second area to a nearby STI isolation region and having a second height, wherein the surface of the said STI isolation region in the first area is lower than the surface of said STI isolation region in the second area.

Abstract: A semiconductor process and apparatus provides an encapsulated shallow trench isolation region by forming a silicon nitride layer (96) to cover a shallow trench isolation region (95), depositing a protective dielectric layer (97, 98) over the silicon nitride layer (96), and polishing and densifying the protective dielectric layer (97, 98) to thereby form a densified silicon nitride encapsulation layer (99) over the shallow trench isolation region (95).

Abstract: A method of performing an STI gapfill process for semiconductor devices is provided. In a specific embodiment of the invention, the method includes forming an stop layer overlying a substrate. In addition, the method includes forming a trench within the substrate, with the trench having sidewalls, a bottom, and a depth. The method additionally includes forming a liner within the trench, the liner lining the sidewalls and bottom of the trench. Furthermore, the method includes filling the trench to a first depth with a first oxide. The first oxide is filled using a spin-on process. The method also includes performing a first densification process on the first oxide within the trench. In addition, the method includes depositing a second oxide within the trench using an HDP process to fill at least the entirety of the trench. The method also includes performing a second densification process on the first and second oxides within the trench.

Abstract: A semiconductor device having high aspect ratio isolation trenches and a method for manufacturing the same is presented. The semiconductor device includes a semiconductor substrate, a first insulation layer, and a second insulation layer. The semiconductor substrate has a second trench that is wider than a first trench. The first insulation layer is partially formed within the wider second trench in which the first insulation layer when formed clogs the opening of the narrower first trench. A cleaning of the first insulation layer unclogs the opening of the narrower first trench in which a second insulation layer can then be formed within both the first and second trenches.

Abstract: A process for the fabrication of a MOSgated device that includes a plurality of spaced trenches in the termination region thereof.

Abstract: An isolation layer structure includes first to fourth oxide layer patterns. The first and third oxide layer patterns are sequentially formed in a first trench defined by a first recessed top surface of a substrate and sidewalls of gate structures on the substrate in a first region. The first trench has a first width, and the first and third oxide layer patterns have no void therein. The second and fourth oxide layer patterns are sequentially formed in a second trench defined by a second recessed top surface of the substrate and sidewalls of gate structures on the substrate in a second region. The second trench has a second width larger than the first width, and the fourth oxide layer pattern has a void therein.

Abstract: Various pattern transfer and etching steps can be used to create features. Conventional photolithography steps can be used in combination with pitch-reduction techniques to form superimposed, pitch-reduced patterns of crossing elongate features that can be consolidated into a single layer. Planarizing techniques using a filler layer and a protective layer are disclosed. Portions of an integrated circuit having different heights can be etched to a common plane.

Abstract: First and second isolation trenches are formed into semiconductive material of a semiconductor substrate. The first isolation trench has a narrowest outermost cross sectional dimension which is less than that of the second isolation trench. An insulative layer is deposited to within the first and second isolation trenches effective to fill remaining volume of the first isolation trench within the semiconductive material but not that of the second isolation trench within the semiconductive material. The insulative layer comprises silicon dioxide deposited from flowing TEOS to the first and second isolation trenches. A spin-on-dielectric is deposited over the silicon dioxide deposited from flowing the TEOS within the second isolation trench within the semiconductive material, but not within the first isolation trench within the semiconductive material. The spin-on-dielectric is deposited effective to fill remaining volume of the second isolation trench within the semiconductive material.

Abstract: A method of fabricating a semiconductor device, the method including forming a buffer oxide layer in a first region and a second region of a semiconductor substrate; forming a plurality of first preliminary mask patterns on the buffer oxide layer in the first region; forming a plurality of second preliminary mask patterns between every two adjacent first preliminary mask patterns from among the plurality of first preliminary mask patterns, respectively; forming a plurality of first mask patterns and a plurality of second mask patterns by trimming the plurality of first preliminary mask patterns and the plurality of second preliminary mask patterns; forming a plurality of first active region mask patterns for exposing the semiconductor substrate; defining a plurality of active regions in the semiconductor substrate by forming a trench including a plurality of first trench spaces having same width as the first space and a plurality of second trench spaces under the second space in the first region; and forming

Abstract: In a semiconductor device and related method of fabricating the same, a hard mask layer is formed over a substrate, portions of the hard mask layer and the substrate are etched to form trenches having protruding portions at sidewalls, and an insulation layer buried in the trenches is formed to form device isolation regions having protruding portions at sidewalls, wherein the device isolation regions decrease a portion of a width of active regions.

Abstract: In methods of forming a trench, first patterns separated from each other by a first width and second patterns separated from each other by a second width are formed on a substrate. The second width is wider than the first width. The substrate is etched using the first patterns and the second patterns to form a first trench having a first depth and a preliminary second trench having a second depth. A sacrificial layer is formed to fill up a space between the first patterns. The substrate is etched using the sacrificial layer to form a second trench having a third depth deeper than the second depth.

Abstract: Techniques for combining nanotechnology with photovoltaics are provided. In one aspect, a method of forming a photovoltaic device is provided comprising the following steps. A plurality of nanowires are formed on a substrate, wherein the plurality of nanowires attached to the substrate comprises a nanowire forest. In the presence of a first doping agent and a first volatile precursor, a first doped semiconductor layer is conformally deposited over the nanowire forest. In the presence of a second doping agent and a second volatile precursor, a second doped semiconductor layer is conformally deposited over the first doped layer. The first doping agent comprises one of an n-type doping agent and a p-type doping agent and the second doping agent comprises a different one of the n-type doping agent and the p-type doping agent from the first doping agent. A transparent electrode layer is deposited over the second doped semiconductor layer.

Abstract: A process for fabrication of a semiconductor device that includes forming a first trench in a semiconductor body, forming spaced spacers in the first trench, and forming a narrower second trench at the bottom of the first trench using the spacers as a mask.

Abstract: Methods of pitch doubling of asymmetric features and semiconductor structures including the same are disclosed. In one embodiment, a single photolithography mask may be used to pitch double three features, for example, of a DRAM array. In one embodiment, two wordlines and a grounded gate over field may be pitch doubled. Semiconductor structures including such features are also disclosed.

Abstract: A method of forming a graded trench for a shallow trench isolation region is provided. The method includes providing a semiconductor substrate with a substrate region. The method further includes forming a pad oxide layer overlying the substrate region. Additionally, the method includes forming an etch stop layer overlying the pad oxide layer. The method further includes patterning the etch stop layer and the pad oxide layer to expose a portion of the substrate region. In addition, the method includes forming a trench within an exposed portion of the substrate region, the trench having sidewalls and a bottom and a first depth. The method additionally includes forming a dielectric layer overlying the trench sidewalls, the trench bottom, and mesa regions adjacent to the trench. The method further includes etching the substrate region to increase the depth of at least a portion of the trench to a second depth.

Abstract: A method of forming an isolation layer of a semiconductor device includes forming first trenches in an isolation region of a semiconductor substrate. Sidewalls and a bottom surface of each of the first trenches are oxidized by a radical oxidization process to form a first oxide layer. An oxidization-prevention spacer is formed on the sidewalls of each of the first trenches. Second trenches are formed in the isolation region below the corresponding first trenches, wherein each second trench is narrower and deeper than the corresponding first trench. The second trenches are filled with a second oxide layer. The first trenches are filled with an insulating layer.

Abstract: A semiconductor device having a dual trench and methods of fabricating the same, a semiconductor module, an electronic circuit board, and an electronic system are provided. The semiconductor device includes a semiconductor substrate having a cell region including a cell trench and a peripheral region including a peripheral trench. The cell trench is filled with a core insulating material layer, and the peripheral trench is filled with a padding insulating material layer conformably formed on an inner surface thereof and a core insulating material layer formed on an inner surface of the padding insulating material layer. The core insulating material layer has a greater fluidity than the padding insulating material layer.

Abstract: An isolation trench structure includes both a deep trench isolation (DTI) trench and a shallow trench isolation (STI) trench. The DTI trench can be formed by etching a deeper, narrower trench in a substrate and filling the deeper trench with one or more materials (such as an oxide). The STI trench can be formed by etching a shallower, wider trench in the substrate and filling the shallower trench with one or more materials (such as an oxide). The STI trench surrounds a portion of the DTI trench, such as by completely encircling an upper portion of the DTI trench. The DTI and STI trenches are filled during different operations, and the DTI and STI trenches can be filled with the same material(s) or with different material(s).

Abstract: A method is disclosed for creating a semiconductor device structure with an oxide-filled large deep trench (OFLDT) portion having trench size TCS and trench depth TCD. A bulk semiconductor layer (BSL) is provided with a thickness BSLT>TCD. A large trench top area (LTTA) is mapped out atop BSL with its geometry equal to OFLDT. The LTTA is partitioned into interspersed, complementary interim areas ITA-A and ITA-B. Numerous interim vertical trenches of depth TCD are created into the top BSL surface by removing bulk semiconductor materials corresponding to ITA-B. The remaining bulk semiconductor materials corresponding to ITA-A are converted into oxide. If any residual space is still left between the so-converted ITA-A, the residual space is filled up with oxide deposition. Importantly, the geometry of all ITA-A and ITA-B should be configured simple and small enough to facilitate fast and efficient processes of oxide conversion and oxide filling.

Abstract: An integrated circuit transistor is fabricated with a trench gate having nonconductive sidewalls. The transistor is surrounded by an isolation trench filled with a nonconductive material. The sidewalls of the gate trench are formed of the nonconductive material and are substantially free of unetched substrate material. As a result, the sidewalls of the gate trench do not form an undesired conductive path between the source and the drain of the transistor, thereby advantageously reducing the amount of parasitic current that flows between the source and drain during operation.

Abstract: A semiconductor device may include, but is not limited to, first and second well regions, and a well isolation region isolating the first and second well regions. The first and second well regions each may include an active region, a device isolation groove that defines the active region, and a device isolation insulating film that fills the device isolation groove. The first and second well regions may include first and second well layers, respectively. The well isolation region may include a well isolation groove, a well isolation insulating film that fills the well isolation groove, and a diffusion stopper layer disposed under a bottom of the well isolation groove. The first and second well layers have first and second bottoms respectively, which are deeper in depth than a bottom of the device isolation groove and shallower in depth than the bottom of the well isolation groove.

Abstract: A method of production of a semiconductor device includes: forming a pattern having open element isolation regions on a first insulating film situated on a semiconductor substrate; forming trenches at the element isolation regions on the semiconductor substrate; forming a second insulating film on the first insulating film and inside the trenches; forming holes in the second insulating film in active regions sectioned by the element isolation regions; and leaving the second insulating film inside the trenches only. An interval between an outer perimeter of each the active regions and an outer perimeter of each of the holes in each of the active regions is set such that the interval in the first circuit region, in which a total area of the active regions is relatively large, is smaller than the interval in the second circuit region, in which the total area of the active regions is relatively small.

Abstract: A method of formation of a microelectromechanical system (MEMS) resonator or filter which is compatible with integration with any analog, digital, or mixed-signal integrated circuit (IC) process, after or concurrently with the formation of the metal interconnect layers in those processes, by virtue of its materials of composition, processing steps, and temperature of fabrication is presented. The MEMS resonator or filter incorporates a lower metal level, which forms the electrodes of the MEMS resonator or filter, that may be shared with any or none of the existing metal interconnect levels on the IC. It further incorporates a resonating member that is comprised of at least one metal layer for electrical connection and electrostatic actuation, and at least one dielectric layer for structural purposes. The gap between the electrodes and the resonating member is created by the deposition and subsequent removal of a sacrificial layer comprised of a carbon-based material.

Abstract: In forming an element isolation trench, an insulating film formed above a semiconductor substrate is etched such that relatively thin insulating film situated in the memory cell region is fully removed whereas relatively thick insulating film situated in the peripheral circuit region is etched so as to leave a remainder insulating film. Then, using the remainder insulating film in the peripheral circuit region as an etch stopper, the semiconductor substrate is etched, whereafter the remainder insulating film in the peripheral circuit region is fully removed to subsequently etch the semiconductor substrate.

Abstract: A method of filling a trench includes: providing a substrate having an upper surface, and a trench extending therein from the upper surface; forming a deposition layer on the substrate in a manner in which the layer partially fills the trench and has a portion which overhangs the trench at the upper surface of the substrate; etching, in a processing chamber, the portion of the deposition layer which overhangs the trench, including by inducing a reaction in the processing chamber using plasma; and subsequently depositing material on the substrate within the partially filled trench, including by inducing a reaction in the processing chamber using plasma.

Abstract: Structures and methods are disclosed for the electrical isolation of semiconductor devices. A method of forming a semiconductor device may include providing a second integrated device region on a substrate that is spaced apart from a first integrated device region. An isolation region may be interposed between the first integrated device region and the second integrated device region. The isolation region may include an isolation recess that projects into the substrate to a first predetermined depth, and that may be extended to a second predetermined depth.

Abstract: A method for manufacturing an integrated circuit including at least one storage cell is provided. The method includes providing a substrate having a first and second side, and a plurality of parallel trenches so that a dividing wall is formed between adjacent trenches, filling the trenches with an insulating compound, providing a first insulating layer having a first and second side on the top surface of the dividing wall, wherein the first side is arranged on the substrate's first side, providing a first conductive layer having a first and second side, wherein the first side is arranged on the insulating layer's second side, wherein the conductive layer protrudes from the substrate surface, providing a second conductive layer having a first and second side, wherein the first side is located on the first conductive layer's second side, and removing parts of the second conductive layer by an anisotropic etching means.

Abstract: The present invention relates to flash memory devices and a method of fabricating the same. In an aspect of the present invention, the flash memory device includes trenches formed in a semiconductor substrate and having a step at their lower portion, a tunnel insulating layer formed in an active region of the semiconductor substrate, first conductive layers formed on the tunnel insulating layer, an isolation layer gap-filling between the trenches and the first conductive layers, and a second conductive layer formed on the first conductive layer and having one side partially overlapping with the isolation layers.

Abstract: A system and method for forming multi recessed shallow trench isolation structures on substrate of an integrated circuit is provided. An integrated circuit includes a substrate, at least two shallow trench isolation (STI) structures formed in the substrate, an oxide fill disposed in the at least two STI structures, and semiconductor devices disposed on the oxide fill in the at least two STI structures. A first STI structure is formed to a first depth and a second STI structure is formed to a second depth. The oxide fill fills the at least two STI structures, and the first depth and the second depth are based on semiconductor device characteristics of semiconductor devices disposed thereon.

Abstract: The invention relates to a method of manufacturing openings in a substrate (5), the method comprising steps of: providing the substrate (5) with a masking layer (40) on a surface thereof; forming a first opening (10), a second opening (30), and a channel (20) in between the first opening (10) and the second opening (30) in the masking layer (40), the channel (20) connecting the first opening (10) with the second opening (30), the second opening (30) having an area (A2) that is larger than the area (A1) of the first opening (10); forming trenches (11, 21, 31) in the substrate (5) located at the first opening (10), the second opening (30), and at the channel (20) under masking of the masking layer (40) by means of anisotropic dry etching, and sealing off the trench (21) located at the channel (20) for forming the openings in the substrate (5). The method of the invention enables formation of a deeper first opening (10) than what is possible with the known methods.

Abstract: A method of making a FET includes forming a gate structure (18), then etching cavities on either side. A SiGe layer (22) is then deposited on the substrate (10) in the cavities, followed by an Si layer (24). A selective etch is then carried out to etch away the SiGe (22) except for a part of the layer under the gate structure (18), and oxide (28) is grown to fill the resulting gap. SiGe source and drains are then deposited in the cavities. The oxide (28) can reduce junction leakage current.

Abstract: A semiconductor memory device having a memory cell region and a peripheral circuit region, and a method of manufacturing such a semiconductor memory device, are proposed, in which trench grooves are formed to be shallow in the memory cell region in order to improve the yield, and trench grooves are formed to be deep in the high voltage transistor region of the peripheral circuit region, in particular in a high voltage transistor region thereof, in order to improve the element isolation withstand voltage. A plurality of memory cell transistors having an ONO layer 15 serving as a charge accumulating insulating layer are provided in the memory cell region, where element isolation grooves 6 for these memory cell transistors are narrow and shallow.

Abstract: The present invention relates to flash memory devices and a method of fabricating the same. In an aspect of the present invention, the flash memory device includes trenches formed in a semiconductor substrate and having a step at their lower portion, a tunnel insulating layer formed in an active region of the semiconductor substrate, first conductive layers formed on the tunnel insulating layer, an isolation layer gap-filling between the trenches and the first conductive layers, and a second conductive layer formed on the first conductive layer and having one side partially overlapping with the isolation layers.

Abstract: A semiconductor device having multiple fin heights is provided. Multiple fin heights are provided by using multiple masks to recess a dielectric layer within a trench formed in a substrate. In another embodiment, an implant mold or e-beam lithography are utilized to form a pattern of trenches in a photoresist material. Subsequent etching steps form corresponding trenches in the underlying substrate. In yet another embodiment, multiple masking layers are used to etch trenches of different heights separately. A dielectric region may be formed along the bottom of the trenches to isolate the fins by performing an ion implant and a subsequent anneal.

Abstract: A method of fabricating a semiconductor device includes forming trench-like recesses in a semiconductor substrate, the recesses including one or more recesses each of which has an opening width of not more than a predetermined value, forming a first insulating film above the substrate after the recesses have been formed, so that one or a plurality of voids are formed in the one or more recesses whose opening widths are not more than the predetermined value, removing part of the first insulating film so that a beam is left which spans the openings so that the beam passes over upper surfaces of the one or more recesses and so that at least the voids are exposed in a portion of the substrate except the beam, and filling the voids in the recesses with a material with fluidity, thereby forming second insulating films in the recesses.

Abstract: A shallow isolation trench structure and methods of forming the same wherein the method of formation comprises a layered structure of a buffer film layer over a dielectric layer which is atop a semiconductor substrate. Tile buffer film layer comprises a material which is oxidation resistant and can be etched selectively to oxide films. The layered structure is patterned with a resist material and etched to form a shallow trench. A thin oxide layer is formed in the trench and the buffer film layer is selectively etched to move the buffer film layer back from the corners of the trench. An isolation material is then used to fill the shallow trench and the buffer film layer is stripped to form an isolation structure. When the structure is etched by subsequent processing step(s), a capped shallow trench isolation structure which covers the shallow trench corners is created.

Abstract: Effective area of a capacitor is to be increased while suppressing increase in number of manufacturing steps. In a semiconductor device, a silicon substrate includes a plurality of first recessed portions having a first depth from the main surface thereof, a second recessed portion provided in a region other than the first recessed portion and having a second depth from the main surface, and a third recessed portion provided in at least one of the plurality of first recessed portions and having a third depth from the bottom portion of the first recessed portion. The second recessed portion and the third recessed portion have the same depth, and a decoupling condenser is provided so as to fill the at least one of the first recessed portion and the third recessed portion provided therein, and an isolation insulating layer is provided so as to fill the remaining first recessed portions, and the second recessed portion is filled with a gate electrode.

Abstract: A metal wiring forming method in a semiconductor device can include forming an interlayer insulating film on a lower metal wiring, the first interlayer insulating film having a non-planar upper surface; forming a stop layer on the interlayer insulating film and over the lower metal wiring; forming an interlayer insulating film pattern on the stop layer, wherein an upper surface of the interlayer insulating film pattern and an upper surface of the stop layer are substantially coplanar; removing a portion of the stop layer to form a stop layer pattern, wherein a portion of the interlayer insulating film over the lower metal wiring is exposed by the stop layer pattern; and etching the exposed portion of the interlayer insulating film to form a via hole therethrough, wherein the lower metal wiring is exposed by the via hole.

Abstract: A method of forming shallow trench isolation (STI) regions for semiconductor devices, the method including defining STI trench openings within a semiconductor substrate; filling the STI trench openings with an initial trench fill material; defining a pattern of nano-scale openings over the substrate, at locations corresponding to the STI trench openings; transferring the pattern of nano-scale openings into the trench fill material so as to define a plurality of vertically oriented nano-scale openings in the trench fill material; and plugging upper portions of the nano-scale openings with additional trench fill material, thereby defining porous STI regions in the substrate.

Abstract: A manufacturing method of a semiconductor device according to an embodiment includes: forming a trench for a device isolation area and a semiconductor projection with a first width by etching a semiconductor substrate; forming an oxide film on the trench and the semiconductor projections; forming an insulating layer on the oxide film; exposing the upper surface of the semiconductor projection by polishing the insulating layer and the oxide film; forming a gate insulating layer at a lower region of the semiconductor projection; and etching the insulating layer and the oxide film on the substrate.

Abstract: A material layer on a substrate being processed, e.g. to form chips, includes one or more functional structures. In order to control pattern density during fabrication of the chip, dummy fill structures of different sizes and shapes are added to the chip at different distances from the functional structures of the material layer. In particular, the placement, size and shape of the dummy structures are determined as a function of a distance to, and density of, the functional structures of the material layer.

Abstract: A semiconductor device includes an element isolation region formed in a semiconductor substrate, an active region surrounded by the element isolation region, and a gate electrode formed in one direction to cross the active region. The semiconductor substrate includes two gate trenches formed in parallel to a major axis direction of the active region in the active region, and a fin-shaped part which is located between the two gate trenches. The gate electrode is buried in the two gate trenches and formed on the fin-shaped part. The fin-shaped part serves as a channel region. A fin field effect transistor in which a width of the channel region is smaller than a gate length is thereby obtained.

Abstract: Provided are a method of forming a device isolation layer and a method of fabricating a semiconductor device. The method includes: forming a first trench and a second trench in a substrate, wherein the second trench is connected to the first trench and has a width smaller than the first trench; forming a liner insulation layer in the second trench such that the liner insulation layer is buried in the second trench; and forming a gap fill insulation layer on the liner insulation layer such that the gap fill insulation layer is buried in the first trench.

Abstract: Roughly described, transistor channel regions are elevated over the level of certain adjacent STI regions. Preferably the STI regions that are transversely adjacent to the diffusion regions are suppressed, as are STI regions that are longitudinally adjacent to N-channel diffusion regions. Preferably STI regions that are longitudinally adjacent to P-channel diffusions are not suppressed; preferably they have an elevation that is at least as high as that of the diffusion regions.

Abstract: A semiconductor device may include, but is not limited to, first and second well regions, and a well isolation region isolating the first and second well regions. The first and second well regions each may include an active region, a device isolation groove that defines the active region, and a device isolation insulating film that fills the device isolation groove. The first and second well regions may include first and second well layers, respectively. The well isolation region may include a well isolation groove, a well isolation insulating film that fills the well isolation groove, and a diffusion stopper layer disposed under a bottom of the well isolation groove. The first and second well layers have first and second bottoms respectively, which are deeper in depth than a bottom of the device isolation groove and shallower in depth than the bottom of the well isolation groove.

Abstract: A semiconductor device having a memory cell area and a peripheral circuit area includes a silicon substrate and an isolation structure implemented by a silicon oxide film formed on a surface of the silicon substrate. A depth of the isolation structure in the memory cell area is smaller than a depth of the isolation structure in the peripheral circuit area, and an isolation height of the isolation structure in the memory cell area is substantially the same as an isolation height of the isolation structure in the peripheral circuit area. Reliability of the semiconductor device can thus be improved.