Abstract: A method of forming a trench device isolation structure, wherein, after forming a trench in a predetermined area of a semiconductor substrate, a lower isolation pattern, an upper liner pattern, and an upper isolation pattern are sequentially formed to fill the trench. A lower device isolation layer is formed on an entire surface of the semiconductor substrate, and then etched to form the lower isolation pattern so that a top surface of the lower isolation pattern is lower than a top surface of the semiconductor substrate. An upper liner layer and an upper device isolation layer are formed on the entire surface of the semiconductor substrate including the lower isolation pattern, and then etched to form the upper liner pattern. As a result, the upper liner pattern covers the top surface of the lower isolation pattern and surrounds the bottom and the sidewall of the upper isolation pattern.

Abstract: A semiconductor device including an insulating film (6) embedded in a concave portion, such as a trench (T) formed on a semiconductor substrate (1) is disclosed. A method of forming a trench isolation structure may include forming a mask layer having a predetermined opening pattern. The mask layer may include a nitride film (3). A trench (T) may be formed through etching using a mask layer as a mask. A thermal oxide film (4) may be formed on an inner wall of a trench (T). An insulating film (11) may be formed on an entire main surface of a semiconductor substrate (1). Insulating film (11) may provide an etching barrier. A nitride film liner (5) may be formed on an insulating film (11). An embedding insulating film (6) may be formed so as to essentially fill trench (T). A planarization treatment may be conducted so as to expose nitride film (3). Nitride film (3) may then be removed by isotropic etching.

Abstract: A method of forming a shallow trench isolation (STI), region in a semiconductor substrate featuring a process sequence that results in desired rounded corners for the sides of active device regions located butting the STI region, has been developed. The process sequence features formation of, followed by removal of, a silicon dioxide layer which was thermally grown in a top portion of the semiconductor substrate, wherein the top portion of semiconductor was subjected to an ion implantation procedure prior to the oxidation procedure. The above process sequence results in a recessed portion of semiconductor located adjacent to unoxidized portions of semiconductor which underlay an oxidation resistant shape, and feature rounded corners. Insulator spacers are then formed on the sides of the oxidation resistant shape, overlying and protecting the rounded comers of subsequent active device regions from a dry etch procedure used to selectively define a shallow trench shape in the exposed semiconductor region.

Abstract: A trench 5 for element separation is formed in a silicon substrate 1 by an etching process using an SiO2 film 2 as a mask (FIG. 1B). Side walls 18 are formed in a manner covering the trench 5 laterally (FIG. 1C). Defect-forming ions such as silicon ions are implanted into the silicon substrate 1 with the SiO2 film 2 and side walls 18 used as a mask, whereby a gettering layer 1 is formed only at a bottom of the trench 5.

Abstract: A dual depth trench isolation structure formed between active devices and conductive well regions of same conductivity type which comprises a first inter-well isolation structure having a first isolation trench depth, a second inter-well isolation structure having a second isolation trench depth which combine to form a dual depth trench containing the dual depth trench isolation structure comprising the first inter-well isolation structure and the second inter-well isolation structure, with the dual depth trench isolation interposed at the boundary of an n-well conductive region and a p-well conductive region, a first intra-well isolation structure having a first isolation trench depth, the first intra-well isolation structure interposed between a pair of p-channel transistors residing in the n-well region, and a second intra-well isolation structure having a second isolation trench depth, the second intra-well isolation structure interposed between a pair of n-channel transistors residing in the p-well regio

Abstract: A semiconductor flash memory device is formed with shallow trench isolation (STI) and a low-resistance source bus line (Vss Bus). Embodiments include forming core and peripheral field oxide regions, as by conventional STI techniques, bit lines by ion implantation, polysilicon floating gates above the channel regions and polysilicon word lines. The Vss Bus is then formed by etching away portions of the field oxide between corresponding source regions of adjacent bit lines to expose portions of the substrate, ion implanting impurities into the source regions and the exposed substrate, forming insulating spacers on the sides of the floating gates and word lines, and forming a metal silicide layer, such as titanium silicide, on the implanted source regions and exposed portions of the substrate to form a continuous conductor between the source regions.

Abstract: The present invention discloses a method for forming a device trench isolation film for a semiconductor device having impurity regions at the sidewalls of the trench. The impurity regions increase the threshold voltage of the transistor and suppress an inverse narrow width effects. In addition, the method prevents or suppresses the phenomenon wherein an impurity in a channel region moves to the trench and lowers the threshold voltage of the transistor, decreases the leakage current, and overcomes a hump phenomenon by turning on a parasitic transistor at the sidewalls with the transistor in the active region. As a result, the electrical properties and reliability of the resulting semiconductor device are improved.

Abstract: A method of forming a flash memory array structure includes forming a first dielectric layer outwardly from a semiconductor substrate, removing a portion of the first dielectric layer and the substrate to create a trench isolation region, forming a second dielectric layer in the trench isolation region, removing a portion of the second dielectric layer to create an exposed substrate region proximate a bottom of the trench isolation region, doping the exposed substrate region with an n-type dopant, and forming a silicide region in the exposed substrate region.

Abstract: A method for manufacturing a semiconductor device in which one active area and another active area formed on an element substrate are electrically isolated from each other includes a first step in which a groove-like area is formed at the element substrate by performing a treatment under conditions whereby the etching rate on a surface {100} is higher than the etching rate on a surface {111} in the area between the one active area and the another active area, and a second step in which the bottom surface of the groove-like area is etched through anisotropic etching. The first step is implemented within a 20 Torr hydrogen gas atmosphere that contains hydrogen chloride gas, and at a temperature of 800 centigrade. The shape of the corner portion formed at the upper end of the trench becomes widened until the angle formed by the side wall and the surface {111} is approximately 144.7 degrees, thereby greatly reducing the concentration of stress at the corner portion.

Abstract: An advanced contact integration technique for deep-sub-150 nm semiconductor devices such as W/WN gate electrodes, dual work function gates, dual gate MOSFETs and SOI devices. This technique integrates self-aligned raised source/drain contact processes with a process employing a W-Salicide combined with ion mixing implantation. The contact integration technique realizes junctions having low contact resistance (RC), with ultra-shallow contact junction depth (XJC) and high doping concentration in the silicide contact interface (Nc).

Abstract: A method and apparatus thereof for fabricating an integrated circuit on a laminate having a gate electrode layer over a silicon dioxide layer. Detection of the gate etch endpoint signal is improved by maximizing the use of a faster etching dopant material (e.g., n-type dopant) and minimizing the use of a slower etching dopant material (e.g., p-type dopant) in the gate electrode layer. In one embodiment, a first portion of the gate electrode layer, substantially corresponding only to the location at which a gate is to be formed, is doped with the slower etching dopant material. The remaining portion of the gate electrode layer is doped with the faster etching dopant material; thus, more of the gate electrode layer is doped with the faster etching dopant material than with the slower etching dopant material. A gate mask is aligned over the gate electrode layer, and the unmasked portions of the gate electrode layer are removed using an etchant.

Abstract: There is disclosed a method of manufacturing a contact plug in a semiconductor device using selective epitaxial growth of silicon (SEG) process. The method includes forming a nitride film at a predetermined in a semiconductor substrate region except for the region in which a contact plug will be formed, forming an USG film on the entire surface of the substrate in which the nitride film is formed by chemical enhanced vapor deposition method or a plasma method, etching the USG film by reactive ion etch method to expose the surface of silicon in the structure, and forming a contact plug by performing in-situ process while performing selective epitaxial growth method for the silicon film exposed through the contact hole in the structure.

Abstract: Semiconductor devices comprising a plurality of active device regions formed in a common semiconductor substrate, e.g., CMOS devices, are formed by utilizing shallow trench isolation (STI) technology enhanced by selectively implanting the bottom surface of the trench with dopant diffusion inhibiting ions prior to filling the trench with a dielectric material and formation of opposite conductivity type well regions on either side of the trench. The inventive methodology effectively reduces or substantially eliminates deleterious counterdoping of the subsequently formed well regions resulting from thermally-induced lateral inter-diffusion of p-type and/or n-type dopant impurities used for forming the well regions.

Abstract: Cesium is implanted into the gate oxide layer of a vertical trench-gated MOSFET. The cesium, which is an electropositive material, reduces the threshold voltage of the device and lowers the on-resistance by improving the accumulation region adjacent the bottom of the trench.

Abstract: The present invention relates to the formation of multiple gettering structures within a semiconductive substrate by ion implantation through recesses in the semiconductive substrate. A preferred embodiment of the present invention includes forming the recesses by using a reactive anisotropic etching medium, followed by implanting a gettering material. The gettering material is implanted by changing the gettering material for the reactive anisotropic etching medium. An advantage of the method of the present invention is that gettering structures are formed without the cost of an extra masking procedure and without the expense of MeV implantation equipment and procedures. As a result, metallic contaminants will not move as freely through the semiconductive substrate in the region of an active area proximal to the gettering structures.

Abstract: A dual depth trench isolation structure formed between active devices and conductive well regions of same conductivity type which comprises a first inter-well isolation structure having a first isolation trench depth, a second inter-well isolation structure having a second isolation trench depth which combine to form a dual depth trench containing the dual depth trench isolation structure comprising the first inter-well isolation structure and the second inter-well isolation structure, with the dual depth trench isolation interposed at the boundary of an n-well conductive region and a p-well conductive region, a first intra-well isolation structure having a first isolation trench depth, the first intra-well isolation structure interposed between a pair of p-channel transistors residing in the n-well region, and a second intra-well isolation structure having a second isolation trench depth, the second intra-well isolation structure interposed between a pair of n-channel transistors residing in the p-well regio

Abstract: Different symmetrical and asymmetrical devices are formed on the same chip using non-critical block masks and angled implants. A barrier is selectively formed adjacent one side of a structure and this barrier blocks dopant implanted at an angle toward the structure. Other structures have no barrier or have two barriers. Source and drain engineering can be performed for LDD, halo, and other desired implants.

Abstract: The semiconductor device has a trench isolation between a P-well and N-well. This trench isolation region is formed of oxide which during the course of the formation of the P and N well is doped with P-type and N-type dopants. Thus the trench has a P-type doped region and an N-type doped region which are typically phosphorous and boron. After the P and N well are formed, a rapid thermal anneal is applied to the device structure. This has the effect of causing the phosphorous doped and boron doped portions of the trench oxide to be etched at substantially the same rate. After this RTA step, gate oxide is formed over the P and N well. The following formation of polysilicon gates results in a relatively flat gate over transistor structure. This avoids corner leakage which is a problem with trench isolation.

Abstract: Different symmetrical and asymmetrical devices are formed on the same chip using non-critical block masks and angled implants. A barrier is selectively formed adjacent one side of a structure and this barrier blocks dopant implanted at an angle toward the structure. Other structures have no barrier or have two barriers. Source and drain engineering can be performed for LDD, halo, and other desired implants.

Abstract: A method for forming a hydrophilic surface on a silicon substrate during cleaning step after well implantation comprises providing a silicon substrate and an insulating layer is deposited thereon for mask alignment requirement. A photoresist layer is formed on the insulating layer and then a well pattern is transferred into the photoresist layer to expose partial the insulating layer thereunder the well defined. Next, implants are implanted into the photoresist layer, the insulating layer and the silicon substrate. Then the insulating layer exposed by the photoresist layer is removed and in-situ a native oxide is formed on the silicon substrate thereunder the well defined whereby changes the surface of the silicon substrate from hydrophobic into hydrophilic. A hard skin on the photoresist layer, resulting from implantation, is removed by oxygen plasma ashing and then the surface of the insulating layer and the silicon substrate are cleaned by conventional technologies.

Abstract: A method (see e.g., FIG. 4) of fabricating a semiconductor device includes forming a trench 12 in a semiconductor body 10. A dielectric layer 26 is formed within the trench 12. Dielectric layer 26 lines the sidewall and, possibly, the bottom portions of the trench 12 in a manner where the thickness of the dielectric 26s at the sidewall is greater than the thickness of the dielectric 26b at the bottom. A dopant 28 can then be implanted into the semiconductor body beneath the trench.

Abstract: A method to implant NMOS polycrystalline silicon in embedded FLASH memory applications is described. In the method the polycrystalline silicon region (130) that will used to form the gate electrode of the NMOS transistor is doped simultaneously along with the source line in the FLASH memory array.

Abstract: A method of fabricating a MOSFET device with a multiple T-shaped gate has the following steps. A substrate with an active region and a non-active region is provided, wherein the active region has a plurality of trenches, and the non-active region has a plurality shallow trench isolation structures. A thin insulating layer and a conducting layer are formed in the trenches. The conducting layer is defined to form a gate. The device is implanted with first ions. Then, the device is further implanted with second ions by using a mask, wherein the mask expose the trenches of the active region, and the opening of the mask is wider than the trench. The MOSFET device has at least the following structures. There is a substrate with an active region and a non-active region, wherein the active region has a plurality of trenches and the non-active region has a plurality of shallow trench isolation structures.

Abstract: A silicon on insulator (SOI) device includes an electrically-conducting interface region along a portion of the interface between the insulator and a semiconductor layer atop the insulator. The electrically-conducting interface region provides a “leaky” electrical coupling between the body and source regions of a transistor device such as a “MOSFET”, thereby reducing floating body effects of the device. A method of forming such a semiconductor device includes forming the electrically-conducting interface region by damaging or implanting materials in the insulator and/or the semiconductor in the vicinity of the interface therebetween. The method may include producing a stepped interface region, such as by etching, in order to aid properly locating the transistor device relative to the electrically-conducting interface region.

Abstract: Semiconductor devices and processes for forming the same. The semiconductor device includes field isolation regions within trenches lying within a semiconductor device substrate. The trenches include a first trench and a second trench. The device includes a first component region and a second component region. The first component region lies near the first trench, and the second component region lies near the second trench. The semiconductor device includes a feature selected from a group consisting of: (a) a first liner within the first trench, and a second liner within the second trench, wherein the first liner is significantly thicker than the second liner; and (b) the first component region has a first edge with a first radius of curvature near the first trench, and the second component has a second edge with a second radius of curvature near the second trench, wherein the first radius of curvature is significantly greater than the second radius of curvature.

Abstract: A method for implanting ions into a surface of a semiconductor structure covered by a layer of insulating material, for example into a trench wall covered by a layer of oxide. A beam of ions is directed at a glancing angle to the layer of insulating material such that a substantial proportion of ions which are implanted into the semiconductor structure surface are scattered from the beam by the layer of insulating material. It is possible therefore to implant ions into a trench wall without requiring a beam source arranged to deliver a beam at a large angle to the trench wall surface.

Abstract: A method of semiconductor device fabrication comprising forming at least the indentation in a surface of a semiconductor body. The indentation is partially filled with a filler material such that walls of the indentation are exposed above an upper surface of the filler material. First and second dopants are introduced through the exposed walls of the indentation and first and second doped regions formed. The first doped region extends into the semiconductor body around the filled portion of the indentation to a first region boundary which is at a predetermined first depth relative to the upper surface of the filler material. The second doped region extends into the semiconductor body around the filled portion of the indentation to a second region boundary which is at a predetermined second depth relative to the upper surface of the filler material.

Abstract: A dielectrically separated wafer and a fabrication method of the same are provided according to the first, second and third embodiments of the present invention.

Abstract: A semiconductor device is disclosed that provides a decoupling capacitance and method for the same. The semiconductor device includes a first circuit region having a first device layer over an isolation layer and a second circuit region adjacent the first circuit region having a second device layer over a well. An implant layer is implanted beneath the isolation layer in the first circuit region, which will connect to the well of the second circuit region.

Abstract: A process for forming high-precision analog transistors with a low threshold voltage roll-up and digital transistors with a high threshold voltage roll-up is disclosed. The process selectively implants the polysilicon layer that forms the gates of the analog transistors so that the doping concentration of the analog gates is greater than the doping concentration of the digital gates.

Abstract: A method for manufacturing a conductive strip includes forming a doped dielectric layer along a surface of a trench. Then, an ion-implanted-sensitive resist is formed over the doped dielectric layer. Next step is to implant ions into the ion-implanted-sensitive resist by substantially vertical implantation such that the ion-implanted-sensitive resist over the lower and upper horizontal surfaces is insoluble portions in a developer and the vertical surface is soluble in the developer. Subsequently, the vertical surface is removed by using the developer and then the doped dielectric layer attached on the vertical surface is also removed. Then, a CMP process is used to remove the ion-implanted-sensitive resist and the doped dielectric layer. Next, a thermal treatment is used to diffuse the dopants in the doped dielectric layer into the lower horizontal surface.

Abstract: A low cost method of manufacturing a silicon substrate having both impurity gettering and protection against CMOS latch up. The method includes performing a low energy implant of a selected acceptor ion to form a low resistivity buried layer closely adjacent the front surface of a silicon wafer. A low energy silicon implant is also performed to create a plurality of gettering sites closely adjacent the front surface. Subsequently, an epitaxial silicon layer is grown on the front surface.

Abstract: A method of connecting a trench capacitor in a dynamic random access memory (DRAM) cell. First, trenches are formed in a silicon substrate using a masking layer including a pad nitride layer on a pad oxide layer. Trench capacitors are formed in the trenches. A buried strap is formed in each trench on the capacitor. The nitride pad layer is pulled back from the trench openings, exposing the pad oxide layer and any strap material that may have replaced the pad oxide layer around the trenches. The straps and trench sidewalls are doped to form a resistive connection. During a subsequent shallow trench isolation (STI) process, which involves an oxidation step, the exposed strap material on the surface of the silicon surface layer forms oxide unrestrained by pad nitride without stressing the silicon substrate.

Abstract: A process for manufacturing deep well junction structures that includes in succession, the steps of: on a first substrate having a first conductivity type and a first doping level, growing an epitaxial layer having the first conductivity type and a second doping level lower than the first doping level; anisotropically etching the epitaxial layer using a mask to form trenches; forming deep conductive regions surrounding the trenches and having a second conductivity type, opposite to the first conductivity type and the second doping level; and filling the trenches. The deep conductive regions are formed by angular ionic implantation and subsequent diffusion of a doping ion species within the epitaxial layer.

Abstract: The method of manufacturing a non-volatile semiconductor memory device comprises a step of providing a first ion implantation on the principal surface of a silicon substrate in a manner to cover a groove to form a first impurity region on the principal surface. Next, a step of providing a second ion implantation to cover the groove to form a second impurity region on the principal surface that overlaps the first impurity region at the groove and electrically connects the second source/drain region and the third source/drain region by the first impurity region. In short, the impurity region at the groove is formed by a twice ion implantation of the first and second ion implantations.

Abstract: A buried layer of dopant is formed in a semiconductor by etching a series of trenches, then depositing dopant at the bottom of the trenches and diffusing until the dopant from different trenches meet to form a continuous layer. Depending on the material used to fill the trenches, the buried layer can be contacted or isolated. With this method, it becomes unnecessary to grow expensive epitaxial layers.

Abstract: A photolithographic process for preventing the rounding of the corners of a pattern. A silicon wafer is provided. A first photoresist layer is formed over the silicon wafer and then patterned to form a first group of mutually parallel photoresist lines along a first direction. A second photoresist layer is formed over the silicon wafer and then patterned to form a second group of mutually parallel photoresist lines along a second direction. The first direction and the second direction are on the same plane but mutually perpendicular.

Abstract: A nonvolatile semiconductor memory cell array is shown which is composed of a plurality of unit cell-arrays arranged in a repeating pattern. Each of the unit cell-arrays includes a first plurality of cell transistors having control gates coupled in common to a first word line and a second plurality of cell transistors having control gates coupled in common to a second word line. The two word lines are arranged in parallel to one another and perpendicular to a bit line. The bit line is connected in common with drains of both the first and second plurality of cell transistors through a bit line contact. A pair of source lines is arranged along each side of the bit line and parallel to the bit line. Each source line is coupled to one transistor from each of the first and second pluralities of cell transistors through a source line contact.

Abstract: A transistor (30) and method for forming a transistor using an edge blocking material (24) is disclosed herein. The edge blocking material (24) may be located adjacent a gate (22) or disposable gate or may be part of a disposable gate. During an angled pocket implant, the edge blocking material (24) blocks some dopant from entering the semiconductor body (10) and the dopant (18) placed under the edge blocking material is located at a given distance below the surface of the semiconductor body (10).

Abstract: A method of forming a semiconductor component having a conductive line (24) that crosses a trench (72). The method involves forming steps (104) in the sidewalls of the trench (72) in a semiconductor substrate (52). A dopant may be implanted at a first energy level into the semiconductor substrate (52) to form a first conductive region (92). The dopant may be implanted at a second energy level into the semiconductor substrate (52) to form a second conductive region (94). The first energy level may be greater than the second energy level. The first conductive region (92) and the second conductive region (94) may form the conductive line (24).

Abstract: The present invention relates to the formation of trench isolation structures that isolate active areas and a preferred doping in the fabrication of a CMOS device with a minimized number of masks. Ions of a P-type dopant are implanted into a semiconductor substrate having therein a P-well and an N-well. Each of the N-well and P-well has therein a trench. The ions of the P-type dopant are implanted beneath each of the trenches in the P-well and the N-well to create a first P-type dopant concentration profile in the semiconductor substrate, wherein the P-well and the N-well are substantially unimplanted by the ions of the P-type dopant in active areas adjacent to the respective trenches therein. A second implanting ions of a P-type dopant is made into the semiconductor substrate. The second implanting is beneath each of the trenches in the P-well and the N-well to form a second P-type dopant concentration profile.

Abstract: The invention provides a method for fabricating a shallow trench isolation which is not susceptable to buried contact trench formation. The invention also provides immunity from the STI “kink effect,” as well as benefits associated with nitridation. The process begins by forming a pad oxide layer on a semiconductor substrate. A nitride layer is formed on the pad oxide layer. The nitride layer, the pad oxide layer, and the semiconductor substrate are patterned to form trenches. Next, a fill oxide layer is formed over the nitride layer, the pad oxide layer, and the semiconductor substrate. The fill oxide layer is chemical-mechanical polished, stopping on the nitride layer to form fill oxide regions. N2 ions are implanted into the fill oxide regions. An anneal is performed to form a buried oxynitride layer. The buried oxynitride layer is partially above the level of the top surface of the semiconductor substrate and partially below the level of the top surface of the semiconductor substrate.

Abstract: A method to reduce the inverse-narrow-line-effect is described in which an active region and an isolation region are defined on a substrate. A doped region is formed adjacent to the substrate surface, wherein the area of the doped region includes the isolation region and the edge of the active region. The depth of the doped region is shallower than that of the source/drain region formed subsequently. A shallow trench is formed thereafter in the isolation region adjacent to the active region, such that the doped region located in the substrate at the edge of the active region is retained. A liner oxide layer is further formed on the inner wall of the shallow trench. An oxide layer, which is as high as the surface of the cap layer, is formed to fill the trench. After the removal of the pad oxide layer and the cap layer, a gate oxide layer and a gate are formed on the substrate.

Abstract: A trench is formed in a semiconductor substrate using a mask. The trench is filled with electrode material, a part of which is removed; alternatively, the trench is partially filled with the electrode material. The side walls of the trench are doped with the mask still in place. After the side walls are doped, the remainder of the trench is filled. The result is a trench gated power device such as a MOSFET, MESFET or IGBT.

Abstract: A method is provided for forming a multiple well of a semiconductor device is provided. By this method, a pocket well region of a first conductivity type is formed over a predetermined first region of a semiconductor substrate of a first conductivity type, using a first photolithography process. A first deep well region of a second conductivity type is then formed under the pocket well region in a self-aligned manner. A peripheral well region of the first conductivity type is selectively formed in a predetermined second region of the semiconductor substrate apart from the pocket well region, using a second photolithography process.

Abstract: The invention encompasses methods of treating semiconductive material wafers and ingots to alleviate slippage within monocrystalline lattices of the wafers and ingots. The invention further encompasses monocrystalline semiconductive material wafers and monocrystalline semiconductive ingots which are treated to alleviate slippage within a crystalline lattice of the wafers and ingots. In one aspect, the invention includes a method of forming a semiconductive material wafer comprising: a) forming an ingot of semiconductive material, said ingot comprising an outer periphery; b) forming a wafer from the ingot, the wafer comprising said outer periphery; and c) doping said outer periphery with strength-enhancing dopant atoms.

Abstract: A method for forming a plurality of buried layers inside a semiconductor device is disclosed. The method includes the following steps. Firstly, a semiconductor substrate is provided. Then, the first type p+-type ions are implanted into the semiconductor substrate to form the p+-type region under the surface of semiconductor substrate. The semiconductor substrate is etched to form a plurality of concave portions and a plurality of convex portions using the first photoresist. The n+-type ions are second implanted into the semiconductor substrate as a plurality of n+-type region. Next, the oxide layer is deposited over the surface of the plurality of concave portions and the surface of the plurality of convex portions. The plurality of n+-type regions are heated to form as the buried layers. The oxide layer is removed. Finally, a silicon layer is formed to fill the plurality of concave of portions a silicon layer and to cover the surface of the plurality of convex portions.

Abstract: A process for top-corner rounding at the rim of shallow trenches of the type used for STI is described. This is achieved by first forming the trench using a silicon nitride hard mask having a layer of pad oxide between itself and the silicon surface. The silicon nitride is then briefly and selectively etched so that it pulls back from over the trench rim and exposes a small amount of the underlying pad oxide. Rounding by means of sputtering is then effected with the pad oxide serving to protect the underlying silicon until just before rounding takes place. The result is smoothly rounded corners free of facets and overhangs.

Abstract: A method of fabricating a flash memory integrated circuit is described. In an embodiment of the present invention a dielectric filled trench isolation region is formed in a silicon substrate. The dielectric filled trench isolation region isolates a first portion of the silicon substrate from a second portion of the silicon substrate. A portion of the dielectric in the trench is then removed to reveal a portion of the silicon substrate in the trench between the first and second portions of the silicon substrate. Ions are then implanted to form a first source region in the first portion of the silicon substrate and to form a second source region in the second portion of the silicon substrate and to form a doped region in the revealed silicon substrate in the trench wherein the doped region in the trench extends from the first doped source region to the second doped source region.

Abstract: A circuit protects against electrostatic discharge and includes a pad which receives an external signal source. The transistor of the present invention is connected to the circuit to be protected and includes a semiconductor body of a first conductivity type and serves as the collector of the transistor and is connected to the pad. A first doped region of a second conductivity type is contained in the semiconductor body and serves as the base of the transistor and forms a collector-to-base junction surface with the semiconductor body. A second doped region of the first conductivity type is contained in the first doped region and serves as the emitter of the transistor and forms a base-to-emitter junction surface with the first doped region. The first and second doped regions are electrically connected for establishing a shorted connection between the base and emitter.