Abstract: A semiconductor process includes the following steps. A substrate having a recess is provided. A decoupled plasma nitridation process is performed to nitride the surface of the recess for forming a nitrogen containing liner on the surface of the recess. A nitrogen containing annealing process is then performed on the nitrogen containing liner.

Abstract: A process for manufacturing a semiconductor transistor device is provided. The process comprises steps of providing a substrate; forming a patterned hard mask on the substrate; forming a spacer on a sidewall of the patterned hard mask; forming a trench by removing a portion of the substrate not being covered by the patterned hard mask and the spacer; and filling a conductive material into the trench.

Abstract: Single spacer processes for multiplying pitch by a factor greater than two are provided. In one embodiment, n, where n?2, tiers of stacked mandrels are formed over a substrate, each of the n tiers comprising a plurality of mandrels substantially parallel to one another. Mandrels at tier n are over and parallel to mandrels at tier n?1, and the distance between adjoining mandrels at tier n is greater than the distance between adjoining mandrels at tier n?1. Spacers are simultaneously formed on sidewalls of the mandrels. Exposed portions of the mandrels are etched away and a pattern of lines defined by the spacers is transferred to the substrate.

Abstract: A method of fabricating a nonvolatile memory device includes providing a substrate having active regions defined by a plurality of trenches, forming a first isolation layer on the substrate having the plurality of trenches, forming a sacrificial layer on the first isolation layer to fill the trenches, the sacrificial layer including a first region filling lower portions of the trenches and a second region filling portions other than the lower portions, removing the second region of the sacrificial layer, forming a second isolation layer on the first isolation layer and the first region of the sacrificial layer, forming air gaps in the trenches by removing the first region of the sacrificial layer, and removing a portion of the first isolation layer and a portion of the second isolation layer while maintaining the air gaps.

Abstract: A FET structure including epitaxial source and drain regions includes large contact areas and exhibits both low resistivity and low parasitic gate to source/drain capacitance. The source and drain regions are laterally etched to provide recesses for accommodating low-k dielectric material without compromising the contact area between the source/drain regions and their associated contacts. A high-k dielectric layer is provided between the raised source/drain regions and a gate conductor as well as between the gate conductor and a substrate, such as an ETSOI or PDSOI substrate. The structure is usable in electronic devices such as MOSFET devices.

Abstract: A method of etching a silicon substrate includes providing a silicon substrate including a first surface and a second surface. A plurality of grooves spaced apart from each other are etched from the first surface of the silicon substrate. A dielectric material is deposited on the first surface of the silicon substrate and into the plurality of grooves. A hole through the silicon substrate is etched from the second surface of the substrate to the dielectric material. A portion of the hole is located between the plurality of grooves.

Abstract: Semiconductor-on-oxide structures and related methods of forming such structures are disclosed. In one case, a method includes: forming a first dielectric layer over a substrate; forming a first conductive layer over the first dielectric layer, the first conductive layer including one of a metal or a silicide; forming a second dielectric layer over the first conductive layer; bonding a donor wafer to the second dielectric layer, the donor wafer including a donor dielectric and a semiconductor layer; cleaving the donor wafer to remove a portion of the donor semiconductor layer; forming at least one semiconductor isolation region from an unremoved portion of the donor semiconductor layer; and forming a contact to the first conductive layer through donor dielectric and the second dielectric layer.

Abstract: The embodiments described provide mechanisms for doping oxide in the STIs with carbon to make etch rate in the narrow and wide structures equal and also to make corners of wide STIs strong. Such carbon doping can be performed by ion beam (ion implant) or by plasma doping. The hard mask layer can be used to protect the silicon underneath from doping. By using the doping mechanism, the even surface topography of silicon and STI enables patterning of gate structures and ILD0 gapfill for advanced processing technology.

Abstract: An active device region is formed in and on a semiconductor substrate. An interconnect layer is formed over the active device region, wherein the interconnect layer comprises a first dielectric material having a first dielectric constant, a first metal interconnect in the first dielectric material, and a second metal interconnect in the first dielectric material and laterally spaced apart from the first metal interconnect. A portion of the first dielectric material is removed such that a remaining portion of the first dielectric material remains within the interconnect layer, wherein the removed portion is removed from a location between the first and second metal interconnects. The location between the first and second metal interconnects from which the portion of the first dielectric material was removed is filled with a second dielectric material having a second dielectric constant, the second dielectric constant being higher than the first dielectric constant.

Abstract: Roughly described, a method for approximating stress-induced mobility enhancement in a channel region in an integrated circuit layout, including approximating the stress at each of a plurality of sample points in the channel, converting the stress approximation at each of the sample points to a respective mobility enhancement value, and averaging the mobility enhancement values at all the sample points. The method enables integrated circuit stress analysis that takes into account stresses contributed by multiple stress generation mechanisms, stresses having vector components other than along the length of the channel, and stress contributions (including mitigations) due to the presence of other structures in the neighborhood of the channel region under study, other than the nearest STI interfaces. The method also enables stress analysis of large layout regions and even full-chip layouts, without incurring the computation costs of a full TCAD simulation.

Abstract: A light emitting diode (LED) module includes a substrate, an LED disposed on the substrate, a phosphor layer disposed on the LED, and a lens disposed on the substrate. The substrate has a recess defined therein. The lens is fastened to the substrate through the recess. A manufacturing method for the LED includes forming the recess in the substrate, mounting the LED on the substrate, forming the phosphor layer on the LED, and forming the lens directly on the substrate such that the lens is fastened to the substrate through the recess.

Abstract: A semiconductor device including a plurality of active patterns, a plurality of first isolation layer patterns and a plurality of second isolation layer patterns may be provided. In particular, the active patterns may be arranged both in a first direction and in a second direction, and may protrude from a substrate and have a length in the first direction. The first isolation layer patterns may fill a first space, the first space provided between the active patterns and arranged in the first direction, and support two opposing sidewalls of neighboring active patterns. The second isolation layer patterns may fill a second space between the active patterns and the first isolation layer patterns. Accordingly, the active patterns of the semiconductor device may not collapse or incline because the first isolation layer patterns support the active patterns.

Abstract: One method disclosed herein includes forming a plurality of fin-formation trenches in a semiconductor substrate that define a plurality of spaced-apart fins, forming a patterned liner layer that covers a portion of the substrate positioned between the fins while exposing portions of the substrate positioned laterally outside of the patterned liner layer, and performing at least one etching process on the exposed portions of the substrate through the patterned liner layer to define an isolation trench in the substrate, wherein the isolation trench has a depth that is greater than a depth of the fin-formation trenches.

Abstract: A charge-trapping NOR (CT-NOR) memory device and methods of fabricating a CT-NOR memory device utilizing silicon-rich nitride (SiRN) in a charge-trapping (CT) layer of the CT-NOR memory device.

Abstract: A base insulating film is formed over a substrate. A first oxide semiconductor film is formed over the base insulating film, and then first heat treatment is performed to form a second oxide semiconductor film. Then, selective etching is performed to form a third oxide semiconductor film. An insulating film is formed over the first insulating film and the third oxide semiconductor film. A surface of the insulating film is polished to expose a surface of the third oxide semiconductor film, so that a sidewall insulating film is formed in contact with at least a side surface of the third oxide semiconductor film. Then, a source electrode and a drain electrode are formed over the sidewall insulating film and the third oxide semiconductor film. A gate insulating film and a gate electrode are formed.

Abstract: A semiconductor device and methods for small trench patterning are disclosed. The device includes a plurality of gate structures and sidewall spacers, an etch stop layer disposed over the sidewall spacers, an interlayer dielectric (ILD) layer disposed on a bottom portion of the etch stop layer, an etch buffer layer disposed on an upper portion of the etch stop layer, and a plurality of metal plugs between the gate structures. An upper portion of the metal plugs is adjacent to the etch buffer layer and a lower portion of the metal plugs is adjacent to the ILD layer.

Abstract: A method of forming a fin structure is provided. First, a substrate is provided, wherein a first region, a second region encompassing the first region, and a third region encompassing the second region are defined on the substrate. Then, a plurality of first trenches having a first depth are formed in the first region and the second region, wherein each two first trenches defines a first fin structure. The first fin structure in the second region is removed. Lastly, the first trenches are deepened to form a plurality of second trenches having a second depth, wherein each two second trenches define a second fin structure. The present invention further provides a structure of a non-planar transistor.

Abstract: A semiconductor device includes a gate structure over a substrate. The device further includes an isolation feature in the substrate and adjacent to an edge of the gate structure. The device also includes a spacer overlying a sidewall of the gate structure. The spacer has a bottom lower than a top surface of the substrate.

Abstract: A method for formation of a sealed shallow trench isolation (STI) region for a semiconductor device includes forming a STI region in a substrate, the STI region comprising a STI fill; forming a sealing recess in the STI fill of the STI region; and forming a sealing layer in the sealing recess over the STI fill.

Abstract: A method of forming a semiconductor-on-insulator (SOI) device includes defining a shallow trench isolation (STI) structure in an SOI substrate, the SOI substrate including a bulk layer, a buried insulator (BOX) layer over the bulk layer, and an SOI layer over the BOX layer; forming a doped region in a portion of the bulk layer corresponding to a lower location of the STI structure, the doped region extending laterally into the bulk layer beneath the BOX layer; selectively etching the doped region of the bulk layer with respect to undoped regions of the bulk layer such that the lower location of the STI structure undercuts the BOX layer; and filling the STI structure with an insulator fill material.

Abstract: A method of manufacturing a semiconductor device is disclosed, which can completely remove hard mask residues left along boundaries between a high-voltage device region and STI structures after a dry etch process, by partially reducing a thickness of each of the exposed portion of the respective STI structures adjacent to the high-voltage device region so as to sufficiently expose the residues. As a result, after a portion of an Underlying pad oxide corresponding to the high-voltage device region is removed in a subsequent process, the exposed surface of the substrate is uniform with a smooth and clear border. Therefore, no sharp corners will emerge at a border of a gate oxide subsequently grown on the exposed surface of the substrate, and the gate oxide is thus morphologically improved, thereby resulting in an improvement of the reliability of the high-voltage semiconductor device being fabricated.

Abstract: Embodiments disclosed describe approaches for providing a local interconnection between a protection diode and a gate transistor in an integrated circuit (IC) device. Specifically, described is an IC device comprising: a protection diode formed in a substrate, a replacement metal gate (RMG) transistor formed over the substrate, a first contact formed over the protection diode (and optional trench silicide layer), a second contact formed over the RMG transistor, wherein the first contact extends to connect directly with the second contact, and a top metal layer (M1) formed over the first contact and the second contact. By extending the first contact from the protection diode directly to the gate transistor as a supplemental interconnect, any charges accumulated during formation of the second contact and the set of vias will be discharged by the protection diode.

Abstract: A method is provided. The method includes forming a plurality of nanowires on a top surface of a substrate and forming an oxide layer adjacent to a bottom surface of each of the plurality of nanowires, wherein the oxide layer is to isolate each of the plurality of nanowires from the substrate.

Abstract: A method for fabricating a semiconductor device is disclosed. An exemplary method includes a providing substrate. A dielectric layer is formed over the semiconductor substrate and a stop layer is formed over the dielectric layer. The stop layer and the dielectric layer comprise a different material. The method further includes forming a patterned hard mask layer over the stop layer and etching the semiconductor substrate through the patterned hard mask layer to form a plurality of trenches. The method also includes depositing an isolation material on the semiconductor substrate and substantially filling the plurality of trenches. Thereafter, performing a CMP process on the semiconductor substrate, wherein the CMP process stops on the stop layer.

Abstract: Semiconductor devices including STI structures and their fabrication methods are provided. A mask layer is provided on a semiconductor substrate and patterned to form an opening in the mask layer to expose a surface portion of the semiconductor substrate. A trench is then formed in the semiconductor substrate by etching along the opening. A first dielectric layer is formed in the trench and has a top surface lower than a top surface of the semiconductor substrate to provide an uncovered sidewall surface of the trench in the semiconductor substrate. An epitaxial layer is formed on the uncovered sidewall surface of the trench in the semiconductor substrate. The epitaxial layer includes a spacing to expose a surface portion of the first dielectric layer. A second dielectric layer is formed on the exposed surface portion of the first dielectric layer to fill the spacing formed in the epitaxial layer.

Abstract: A trench isolation method is disclosed. A substrate having thereon a pad layer and a hard mask is provided. An opening is formed in the hard mask. The substrate is etched through the opening to thereby form a first trench. A spacer is formed on a sidewall of the first trench. A second trench is then etched into the substrate through the first trench by using the spacer as an etching hard mask. The substrate within the second trench is then oxidized by using the spacer as an oxidation protection layer, thereby forming an oxide layer that fills the second trench. The spacer is then removed to reveal the sidewall of the first trench. A liner layer is then formed on the revealed sidewall of the first trench. A chemical vapor deposition process is then performed to deposit a dielectric layer that fills the first trench.

Abstract: Disclosed is an integrated circuit die comprising an active substrate including a plurality of components laterally separated from each other by respective isolation structures, at least some of the isolation structures carrying a further component, wherein the respective portions of the active substrate underneath the isolation structures carrying said further components are electrically insulated from said components. A method of manufacturing such an IC die is also disclosed.

Abstract: A method of forming a fin structure of a semiconductor device includes providing a substrate, creating a mandrel pattern over the substrate, depositing a first spacer layer over the mandrel pattern, and removing portions of the first spacer layer to form first spacer fins. The method also includes performing a first fin cut process to remove a subset of the first spacer fins, depositing a second spacer layer over the un-removed first spacer fins, and removing portions of the second spacer layer to form second spacer fins. The method further includes forming fin structures, and performing a second fin cut process to remove a subset of the fin structures.

Abstract: A method of forming a semiconductor device includes defining a first type region and a second type region in a substrate, t separated by one or more inter-well STI structures; etching and filling, in at least one of the first type region and the second type region, one or more intra-well STI structures for isolating semiconductor devices formed within a same polarity well, wherein the one or more inter-well STI structures are formed at a substantially same depth with respect to the one or more intra-well STI structures; implanting, a main well region, wherein a bottom of the main well region is disposed above a bottom of the one or more inter-well and intra-well STI features; and implanting, one or more deep well regions that couple main well regions, wherein the one or more deep well regions are spaced away from the one or more inter-well STI structures.

Abstract: Embodiments herein provide approaches for forming a diffusion break during a replacement metal gate process. Specifically, a semiconductor device is provided with a set of replacement metal gate (RMG) structures over a set of fins patterned from a substrate; a dielectric material over an epitaxial junction area; an opening formed between the set of RMG structures and through the set of fins, wherein the opening extends through the dielectric material, the expitaxial junction area, and into the substrate; and silicon nitride (SiN) deposited within the opening to form the diffusion break.

Abstract: The invention relates to a semiconductor device and a method for manufacturing such a semiconductor device. A semiconductor device according to an embodiment of the invention may comprise: a substrate; a device region located on the substrate; and at least one stress introduction region separated from the device region by an isolation structure, with stress introduced into at least a portion of the at least one stress introduction region, wherein the stress introduced into the at least a portion of the at least one stress introduction region is produced by utilizing laser to illuminate an amorphized portion comprised in the at least one stress introduction region to recrystallize the amorphized portion. The semiconductor device according to an embodiment of the invention produces stress in a simpler manner and thereby improves the performance of the device.

Abstract: A mold having an open interior volume is used to define patterns. The mold has a ceiling, floor and sidewalls that define the interior volume and inhibit deposition. One end of the mold is open and an opposite end has a sidewall that acts as a seed sidewall. A first material is deposited on the seed sidewall. A second material is deposited on the deposited first material. The deposition of the first and second materials is alternated, thereby forming alternating rows of the first and second materials in the interior volume. The mold and seed layer are subsequently selectively removed. In addition, one of the first or second materials is selectively removed, thereby forming a pattern including free-standing rows of the remaining material. The free-standing rows can be utilized as structures in a final product, e.g., an integrated circuit, or can be used as hard mask structures to pattern an underlying substrate. The mold and rows of material can be formed on multiple levels.

Abstract: A device and method of reducing residual STI corner defects in a hybrid orientation transistor comprising, forming a direct silicon bonded substrate wherein a second silicon layer with a second crystal orientation is bonded to a handle substrate with a first crystal orientation, forming a pad oxide layer on the second silicon layer, forming a nitride layer on the pad oxide layer, forming an isolation trench within the direct silicon bonded substrate through the second silicon layer and into the handle substrate, patterning a PMOS region of the direct silicon bonded substrate utilizing photoresist including a portion of the isolation trench, implanting and amorphizing an NMOS region of the direct silicon bonded substrate, removing the photoresist, performing solid phase epitaxy, performing a recrystallization anneal, forming an STI liner, completing front end processing, and performing back end processing.

Abstract: An embodiment of the disclosure includes a method of forming a semiconductor structure. A substrate has a region adjacent to a shallow trench isolation (STI) structure in the substrate. A patterned mask layer is formed over the substrate. The patterned mask layer covers the STI structure and a portion of the region, and leaves a remaining portion of the region exposed. A distance between an edge of the remaining portion and an edge of the STI structure is substantially longer than 1 nm. The remaining portion of the region is etched thereby forms a recess in the substrate. A stressor is epitaxially grown in the recess. A conductive plug contacting the stressor is formed.

Abstract: An aspect of the present embodiment, there is provided a method of manufacturing a semiconductor device, the method includes providing trenches in an end terminal area of a substrate, the end terminal area surrounding an element area of the a substrate, the trenches surrounding the element area, filling a fluent material mixed with carbonate, oxide and solvent in the each of the trenches, burning the fluent material in the trench to embed an insulator in the trench, and providing an element unit in the element area.

Abstract: A semiconductor device includes a memory cell transistor that is formed via a first gate insulating film on an active region of a memory cell region and has a gate electrode including a first charge storage layer, a first interelectrode insulating film, and a first control gate electrode film. A transistor, which includes a second gate insulating film on the active region or a peripheral circuit region and a gate electrode including a second charge storage layer, a second interelectrode insulating film, and a second control gate electrode film, is also provided. A groove with a funnel shape is formed in a trap film of the second charge storage layer, and the second control gate electrode film and the polysilicon film of the second charge storage layer are interconnected via the groove.

Abstract: In general, according to one embodiment, a nonvolatile semiconductor memory device includes a memory cell region and a peripheral region. The memory cell region includes first element isolation regions, first semiconductor regions, a first gate insulating film, a charge storage layer, a second gate insulating film, and a control gate electrode. The first element isolation regions separate a semiconductor layer and include a first insulating film. The first semiconductor regions are separated by the first element isolation regions. The peripheral region includes a second element isolation region a second insulating film. Each of the first element isolation regions includes a first and a second portion. A step is present between the first and the second portion. At least part of a side surface and a lower end of the second element isolation region are surrounded by the semiconductor layer.

Abstract: A semiconductor device of the present invention is a semiconductor device selectively including a nonvolatile memory cell on a semiconductor substrate, and includes a trench formed in the semiconductor substrate, an element separation portion buried into the trench such that the element separation portion has a projecting part projecting from the semiconductor substrate, the element separation portion defining an active region in first a region for the nonvolatile memory cell of the semiconductor substrate, and a floating gate disposed in the active region such that the floating gate selectively has an overlapping part overlapping the element separation portion, and the floating gate has a shape recessed with respect to the overlapping part.

Abstract: A method of forming a semiconductor device is provided. The method includes preparing a substrate having a transistor region and an alignment region, forming a first trench and a second trench in the substrate of the transistor region and in the substrate of the alignment region, respectively, forming a drift region in the substrate of the transistor region, forming two third trenches respectively adjacent to two ends of the drift region, and forming an isolation pattern in the first trench, a buried dielectric pattern in the second trench, and dielectric patterns in the two third trenches, respectively. A depth of the first trench is less than a depth of the third trenches, and the depth of the first trench is equal or substantially equal to a depth of the second trench.

Abstract: The present invention provides a method for forming a fin structure comprising the following steps: first, a multiple-layer structure is formed on a substrate; then, a sacrificial pattern is formed on the multiple-layer structure, a spacer is formed on the sidewall of the sacrificial pattern and disposed on the multiple-layer structure, the sacrificial pattern is removed, the spacer is used as a cap layer to etch parts of the multiple-layer structure, and then the multiple-layer structure is used as a cap layer to etch the substrate and to form at least one fin structure in the substrate.

Abstract: Disclosed is a method for manufacturing an oxide thin film transistor, including: forming a gate electrode on a substrate on which a buffer layer is formed; forming a gate insulation layer on an entire surface of the substrate on which the gate electrode is formed; forming an oxide semiconductor layer on the gate insulation layer; forming a first etch stop layer on the oxide semiconductor layer; forming a second etch stop layer on the first etch stop layer by an atomic layer deposition method; patterning the first etch stop layer and the second etch stop layer, or forming a contact hole, through which a part of the oxide semiconductor layer is exposed, in the first etch stop layer and the second etch stop layer; forming a source electrode and a drain electrode on the first etch stop layer and the second etch stop layer; and forming a passivation layer on the entire surface of the substrate on which the source electrode and the drain electrode are formed.

Abstract: A semiconductor device is provided having reduced corner thinning in a shallow trench isolation (STI) structure of the periphery region. The semiconductor device may be substantially free of any corner thinning at a corner of a STI structure of the periphery region. Methods of manufacturing such a semiconductor device are also provided.

Abstract: The embodiments described provide methods and semiconductor device areas for etching an active area region on a semiconductor body and epitaxially depositing a semiconductor layer overlying the active region. The methods enable the mitigation or elimination of problems encountered in subsequent manufacturing associated with STI divots.

Abstract: A semiconductor device includes a substrate with an active pattern, the active pattern having a first extension portion extending in a first direction substantially parallel to a top surface of the substrate, a second extension portion extending from a first end of the first extension portion in a third direction oriented obliquely to the first direction, a third extension portion extending from a second end of the first extension portion in a direction opposed to the third direction, a first projection portion protruding from the second extension portion in a direction opposed to the first direction, the first projection portion being spaced apart from the first extension portion, and a second projection portion protruding from the third extension portion in the first direction, the second projection portion being spaced apart from the first extension portion.

Abstract: An embodiment is a semiconductor structure. The semiconductor structure comprises at least two gate structures on a substrate. The gate structures define a recess between the gate structures, and the recess is defined by a depth in a vertical direction. The depth is from a top surface of at least one of the gate structures to below a top surface of the substrate, and the depth extends in an isolation region in the substrate. The semiconductor structure further comprises a filler material in the recess. The filler material has a first thickness in the vertical direction. The semiconductor structure also comprises an inter-layer dielectric layer in the recess and over the filler material. The inter-layer dielectric layer has a second thickness in the vertical direction below the top surface of the at least one of the gate structures. The first thickness is greater than the second thickness.

Abstract: Disclosed are methods for forming a localized buried dielectric layer under a fin for use in a semiconductor device. In some embodiments, the method may include providing a substrate comprising a bulk semiconductor material and forming at least two trenches in the substrate, thereby forming at least one fin. The method further includes filling the trenches with an insulating material and partially removing the insulating material to form an insulating region at the bottom of each of the trenches. The method further includes depositing a liner at least on the sidewalls of the trenches, removing a layer from a top of each of the insulating regions to thereby form a window opening at the bottom region of the fin, and transforming the bulk semiconductor material of the bottom region of the fin via the window opening, thereby forming a localized buried dielectric layer in the bottom region of the fin.

Abstract: A method including forming an isolation trench; forming first and second liners on the isolation trench; filling the isolation trench an insulating material to form an isolation region and an active region; forming a preliminary gate trench including a first region across the isolation region to expose the first liner, the second liner, and the insulating material, and a second region across the active region to expose a portion of the substrate, the first region having a first sidewall with a planar shape, and the second region having a second sidewall with a concave central area such that an interface between the first and second regions has a pointed portion; removing a portion of the first liner exposed by the first region to form a dent having a first depth by which the pointed portion protrudes; removing the pointed portion to form a gate trench; and forming a gate electrode.

Abstract: According to one embodiment, a semiconductor memory device includes a substrate, an upper-layer wire provided on the substrate, a lower-layer wire provided on the substrate, a memory cell located at an intersection of the upper-layer wire and the lower-layer wire and includes a diode and a storage layer, a conductive layer located between the upper-layer wire and the memory cell in a direction perpendicular to the substrate surface, and an interlayer insulating film provided between memory cells. The position of an interface between the upper-layer wire and the interlayer insulating film is lower than a top surface of the conductive layer.

Abstract: A method of manufacturing a semiconductor device includes forming isolation layers in a first direction at trenches at isolation regions defined at a semiconductor substrate and forming gate lines in a second direction crossing the first direction over the isolation layers and active regions defined between the isolation layers, performing a dry-etch process to remove the isolation layers, and forming an insulating layer over the semiconductor substrate to form a first air gap extending in the first direction in the trenches and a second air gap extending in the second direction between the gate lines.

Abstract: A semiconductor device includes a substrate and a gate structure formed over the substrate. The semiconductor device further includes an insulator feature formed in the substrate. The insulator feature includes an insulating layer and a capping layer over the insulating layer.