Abstract: An structure for electrically isolating a semiconductor device is formed by implanting dopant into a semiconductor substrate that does not include an epitaxial layer. Following the implant the structure is exposed to a very limited thermal budget so that dopant does not diffuse significantly. As a result, the dimensions of the isolation structure are limited and defined, thereby allowing a higher packing density than obtainable using conventional processes which include the growth of an epitaxial layer and diffusion of the dopants. In one group of embodiments, the isolation structure includes a deep layer and a sidewall which together form a cup-shaped structure surrounding an enclosed region in which the isolated semiconductor device may be formed. The sidewalls may be formed by a series of pulsed implants at different energies, thereby creating a stack of overlapping implanted regions.

Abstract: A method of manufacturing a semiconductor device includes: (A) a wafer process; and (B) a bias application process after the wafer process. The wafer process includes: (a) forming a n-type well in a p-type semiconductor substrate; (b) forming a p-type well in the n-type well; and (c) forming a transistor on the p-type well, the transistor having a n-type source/drain diffusion layer. In the bias application process, a forward bias is applied between the p-type well and the n-type well to move heavy metal ions.

Abstract: A semiconductor structure and method of manufacturing is provided. The method of manufacturing includes forming shallow trench isolation (STI) in a substrate and providing a first material and a second material on the substrate. The first material and the second material are mixed into the substrate by a thermal anneal process to form a first island and second island at an nFET region and a pFET region, respectively. A layer of different material is formed on the first island and the second island. The STI relaxes and facilitates the relaxation of the first island and the second island. The first material may be deposited or grown Ge material and the second material may deposited or grown Si:C or C. A strained Si layer is formed on at least one of the first island and the second island.

Abstract: A memory transistor having a pair of separate floating gates overlying end regions of a channel and a control gate that overlies the floating gates and a central region of the channel effectively operates as a pair of floating gate transistors with an intervening select transistor. Each floating gate can be charged to store a distinct binary, analog, or multi-bit value. An erase operation can use a negative voltage on the control and a positive voltage on an underlying well or source/drain region to cause tunneling that discharges one or both floating gates. Applying a limited current to a source/drain region during an erase operation can cause the source/drain region and a floating gate to rise together and avoid band-to-band tunneling and resulting hole injection into the floating gate.

Abstract: A method of fabricating an LDMOS transistor and a conventional CMOS transistor together on a substrate. A P-body is implanted into a source region of the LDMOS transistor. A gate oxide for the conventional CMOS transistor is formed after implanting the P-body into the source region of the LDMOS transistor. A fixed thermal cycle associated with forming the gate oxide of the conventional CMOS transistor is not substantially affected by the implanting of the P-body into the source region of the LDMOS transistor.

Abstract: In a multiple input ESD protection structure, the inputs are isolated from the substrate by highly doped regions of opposite polarity to the input regions. Dual polarity is achieved by providing a symmetrical structure with n+ and p+ regions forming each dual polarity input. The inputs are formed in a p-well which, in turn, is formed in a n-well. Each dual polarity input is isolated by a PBL under the p-well, and a NISO underneath the n-well. An isolation ring separates and surrounds the inputs. The isolation ring comprises a p+ ring or a p+ region, n+ region, and p+ region formed into adjacent rings.

Abstract: A method for forming a CMOS well structure including forming a plurality of first conductivity type wells over a substrate, each of the plurality of first conductivity type wells formed in a respective opening in a first mask. A cap is formed over each of the first conductivity type wells, and the first mask is removed. Sidewall spacers are formed on sidewalls of each of the first conductivity type wells. A plurality of second conductivity type wells are formed, each of the plurality of second conductivity type wells are formed between respective first conductivity type wells. A plurality of shallow trench isolations are formed between the first conductivity type wells and second conductive type wells. The plurality of first conductivity type wells are formed by a first selective epitaxial growth process, and the plurality of second conductivity type wells are formed by a second selective epitaxial growth process.

Abstract: A method is provided for manufacturing a semiconductor device that can reduce the number of steps in manufacturing a triple-well that includes multiple ion implantation steps and heat treatment steps.

Abstract: A semiconductor device comprising a buried insulating film formed in a substrate; a protective film formed on the buried insulating film covering corresponding diffusion regions of a P-type MISFET and a N-type MISFET, wherein the protective film is etch resistant to a hydrofluoric acid based solution; and a wiring layer formed on the protective film and being electrically connecting the diffusion regions of the P-type MISFET and the N-type MISFET.

Abstract: A structure and method are provided in which a stress present in a film is reduced in magnitude by oxidizing the film through atomic oxygen supplied to a surface of the film. In an embodiment, a mask is used to selectively block portions of the film so that the stress is relaxed only in areas exposed to the oxidation process. A structure and method are further provided in which a film having a stress is formed over source and drain regions of an NFET and a PFET. The stress present in the film over the source and drain regions of either the NFET or the PFET is then relaxed by oxidizing the film through exposure to atomic oxygen to provide enhanced mobility in at least one of the NFET or the PFET while maintaining desirable mobility in the other of the NFET and PFET.

Abstract: For characterizing bulk leakage current of a junction, a center junction surrounded by an isolation structure is formed with a first depth. In addition, at least one periphery junction having a second depth greater than the first depth is formed in a portion of the center junction adjacent the isolation structure. A junction silicide is formed with the center and periphery junctions. The magnitude of a reverse-bias voltage across the junction silicide and the P-well is incremented for determining a critical magnitude of the reverse-bias when current through the junction silicide and the P-well reaches a threshold current density.

Abstract: The threshold voltage shift exhibited by strained silicon NMOS devices is compensated with respect to the threshold voltages of PMOS devices formed on the same substrate by increasing the work function of the NMOS gates. The NMOS gate work function exceeds the PMOS gate work function so as to compensate for a difference in the respective NMOS and PMOS threshold voltages. The NMOS gates are preferably fully silicided while the PMOS gates are partially silicided.

Abstract: A method of forming a semiconductor device includes forming a body region of a semiconductor substrate and forming a drift region adjacent at least a portion of the body region. A dopant is used to form the drift region. The dopant may comprise phosphorous. The method also includes forming a field oxide structure adjacent a portion of the drift region and a portion of a drain region. The field oxide structure is located between a gate electrode region and the drain region and is spaced apart from the gate electrode region. Atoms of the dopant accumulate adjacent a portion of the field oxide structure, forming an intermediate-doped region adjacent a portion of the field oxide structure. The method includes forming a gate oxide adjacent a portion of the body region and forming a gate electrode adjacent a portion of the gate oxide.

Abstract: A manufacturing method of a semiconductor device disclosed herein, comprises: forming a buried insulating film in a semiconductor substrate; forming semiconductor elements isolated by the buried insulating film; cleaning a surface side of the semiconductor substrate with a cleaning solution; and covering a surface side of the buried insulating film with a protective film before the step of cleaning the surface side of the semiconductor substrate, wherein a protective film is resistant to the cleaning solution.

Abstract: An LDMOS transistor and a bipolar transistor with LDMOS structures are disclosed for suitable use in high withstand voltage device applications, among others. The LDMOS transistor includes a drain well region 21 formed in P-type substrate 1, and also formed therein spatially separated one another are a channel well region 23 and a medium concentration drain region 24 having an impurity concentration larger than that of drain well region 21, which are simultaneously formed having a large diffusion depth through thermal processing. A source 11s is formed in channel well region 23, while a drain 11d is formed in drain region 24 having an impurity concentration larger than that of drain region 24. In addition, a gate electrode 11g is formed over the well region, overlying the partially overlapped portions with well region 23 and drain region 24 and being separated from drain 11d.

Abstract: LDMOS transistor devices and fabrication methods are provided, in which additional dopants are provided to region of a substrate near a thick dielectric between the channel and the drain to reduce device resistance without significantly impacting breakdown voltage. The extra dopants are added by implantation prior to formation of the thick dielectric, such as before oxidizing silicon in a LOCOS process or following trench formation and before filling the trench in an STI process.

Abstract: A semiconductor fabrication process includes forming first and second transistors over first and second well regions, respectively where the first transistor has a first gate dielectric and the second transistor has a second gate dielectric different from the first gate dielectric. The first transistor has a first gate electrode and the second transistor has a second gate electrode. The first and second gate electrodes are the same in composition. The first gate dielectric and the second gate dielectric may both include high-K dielectrics such as Hafnium oxide and Aluminum oxide. The first and second gate electrodes both include a gate electrode layer overlying the respective gate dielectrics. The gate electrode layer is preferably either TaSiN and TaC. The first and second gate electrodes may both include a conductive layer overlying the gate electrode layer. In one such embodiment, the conductive layer may include polysilicon and tungsten.

Abstract: A method is provided for manufacturing a semiconductor device having a high breakdown voltage transistor and a low breakdown voltage transistor with different driving voltages provided in a common substrate. The method includes: (a) introducing a first impurity of a second conductivity type by an ion implantation in a specified region of a semiconductor substrate of a first conductivity type; (b) forming an oxide film on a surface of the semiconductor substrate, and diffusing the first impurity by a heat treatment in an atmosphere that does not include oxygen to form a first well of the second conductivity type; and (c) introducing a second impurity of the first conductivity type through the oxide film in a specified region of the first well, and diffusing the second impurity by a heat treatment to form a second well of the first conductivity type.

Abstract: This invention provides a manufacturing method for fabricating on the same substrate both high voltage thin film transistors suitable for driving liquid crystal and low voltage drive high performance thin film transistors. In addition, this invention provides a thin film transistor substrate where the area occupied by a storage capacitor in each pixel is reduced to raise the aperture ratio of the display unit. One aspect of this invention provides a manufacturing method characterized in that the impurity regions of both high voltage thin film transistors and high performance thin film transistors which differ in the thickness of gate insulation are formed by implanting a dopant through the same two-layered film. Another aspect of this invention reduces the area occupied by the drive circuit in the display unit by utilizing an extension of one layer of the insulation film included in each thin film transistor.

Abstract: A semiconductor device includes a relatively lower threshold level MOSFET and relatively higher threshold level MOSFETs of n- and p-types. The higher threshold level MOSFETs have gate oxide films which is thicker than that of the lower threshold level MOSFET and, in addition, the gate oxide film of the higher threshold level MOSFET of n-type is thicker than that of the higher threshold level MOSFET of p-type. To fabricate the semiconductor device, implantation treatments of fluorine ions are carried out before the gate oxide treatment. Specifically, as for the higher threshold level MOSFETs of n- and p-types, implantation treatments of fluorine ions are independently carried out with unique implantation conditions.

Abstract: A method for fabricating a metal oxide semiconductor (MOS) transistor, which can reduce the junction capacitance without degradation of transistor characteristics including forming a buffer oxide layer on a semiconductor substrate; successively conducting ion implantations for well formation and field stop formation in the substrate through the buffer oxide layer; removing the buffer oxide layer; forming and patterning a sacrificial layer to form a trench successively conducting ion implantations for threshold voltage adjustment and punch stop formation on the semiconductor substrate area exposed by the trench; forming a gate oxide layer on the exposed surface of the substrate; forming a polysilicon layer so as to completely fill the trench; polishing the polysilicon layer to form a gate electrode; removing the sacrificial layer; forming an LDD region in the substrate; forming spacers on side walls of the gate electrode; and forming source/drain regions.

Abstract: A semiconductor device with p-channel and n-channel field effect devices formed on a common substrate, where the drain and source regions of the n-channel field effect device are formed within a silicon epitaxial layer formed on a silicon layer germanium relax which is formed on a silicon germanium buffer layer with a graduated germanium concentration. Additionally, drain and source regions of the p-channel field effect device are formed within a silicon-germanium compound layer formed on the substrate and the silicon epitaxial cap layer formed on the silicon-germanium compound layer.

Abstract: The invention provides integrated semiconductor devices that are formed upon an SOI substrate having different crystal orientations that provide optimal performance for a specific device. Specifically, an integrated semiconductor structure including at least an SOI substrate having a top semiconductor layer of a first crystallographic orientation and a semiconductor material of a second crystallographic orientation, wherein the semiconductor material is substantially coplanar and of substantially the same thickness as that of the top semiconductor layer and the first crystallographic orientation is different from the second crystallographic orientation is provided. The SOI substrate is formed by forming an opening into a structure that includes at least a first semiconductor layer and a second semiconductor layer that have different crystal orientations. The opening extends to the first semiconductor layer.

Abstract: A method for forming a lateral SCR device for on-chip ESD protection in shallow-trench-isolation CMOS process is provided. In the present lateral SCR device, the shallow trench isolation among the current conduction path of the lateral SCR device is removed and instead of a dummy gate. Thereby, the SCR device has a narrower anode-to-cathode spacing, and then the lateral SCR device can be turned on more quickly to protect the CMOS IC's in ESD events. Additionally, the silicon area of the substrate occupied by the lateral SCR device is also saved. This method for forming a lateral SCR device without shallow-trench-isolation regions in its current path can be fully process-compatible to general CMOS technologies by only changing layout patterns in the mask layers.

Abstract: A high performance super-minituarized double gate SOIMOS being fabricated by re-distributing the impurity with high concentration at the interface of a buried gate insulative film and by aligning the double gate in a self-aligned manner and furthermore, by isolating completely the buried gate electrodes electrically from each other, in which a multi-layered SOI substrate having an amorphous or polycrystal semiconductor layer constituted by way of a buried gate insulative film to a lower portion of an SOI layer is used, ion implantation is applied to the semiconductor layer in a pattern opposite to the upper gate electrode and the buried gate is constituted in a self-alignment relation with the upper gate.

Abstract: A semiconductor device with dynamic threshold transistors includes a complex element isolation region composed of a shallow element isolation region made of shallow trench isolation and deep element isolation regions provided on both sides of the shallow element isolation region. Since the shallow element isolation region is made of the shallow trench isolation, Bird's beak in the shallow element isolation region is small. This prevents off leakage failure due to stress caused by the bird's beak. The deep element isolation region has an approximately constant width which allows the complex element isolation region to be wide.

Abstract: Dynamic Random Access Memory (DRAM) cells are formed in a P well formed in a biased deep N well (DNW). PMOS transistors are formed in N wells. The NMOS channels stop implant mask is modified not to be a reverse of the N well mask in order to block the channels stop implant from an N+ contact region used for DNW biasing. In DRAMs and other integrated circuits, a minimal spacing requirement between a well of an integrated circuit on the one hand and adjacent circuitry on the other hand is eliminated by laying out the adjacent circuitry so that the well is located adjacent to a transistor having an electrode connected to the same voltage as the voltage that biases the well. For example, in DRAMs, the minimal spacing requirement between the DNW and the read/write circuitry is eliminated by locating the DNW next to a transistor precharging the bit lines before memory accesses. One electrode of the transistor is connected to a precharge voltage.

Abstract: A semiconductor device and method of manufacturing the semiconductor device including a semiconductor substrate of a first conductivity type. A scribe lane area formed in the substrate to define chip formation areas. A deep well area formed in each chip formation area. The deep well area has a second conductivity type which is opposite the first conductivity type. Also, at least one well area is formed within the deep well area.

Abstract: A method for fabricating a CMOS transistor is disclosed. The present invention provides a method for producing a CMOS transistor having enhanced performance since a short channel characteristic and operation power can be controlled by the duplicate punch stop layer of the pMOS region and the operation power of the nMOS is also controlled by dopant concentration of the duplicated LDD region combined by the first LDD region and the second LDD region.

Abstract: A deep submicron MOS transistor is formed with multiple control gates by forming side wall control gates adjacent to the gate oxide spacers over heavily-doped regions of the source and drain regions. The side wall control gates can be used to substantially increase the threshold voltage of the transistor.

Abstract: A method of manufacturing a power switching transistor for a fluid ejection device includes forming a diffused drain region and a diffused source region separated by a channel region. The diffused drain region and the diffused source region are doped with a first dopant. A first portion of the diffused drain region is doped with a second dopant, such that the first portion of the diffused drain region has a greater impurity concentration than at least a second portion of the diffused drain region and has a greater impurity concentration than the diffused source region.

Abstract: A method for fabricating source/drain devices. A semiconductor substrate is provided with a gate formed thereon, a first doped area is formed on a first side of the gate on the semiconductor substrate, and a second doped area is formed on a second side of the gate on the semiconductor substrate in a manner such that the second doped area is separated from the gate by a predetermined distance. A patterned photo resist layer is formed on the semiconductor substrate having an opening on the second side, the exposed gate less than half the width of the gate. The semiconductor substrate is implanted and annealed to form a dual diffusion area on the second side of the gate using the patterned photo resist layer as a mask.

Abstract: A gate oxide film and a first layer of a multilayered gate electrode are stacked on a substrate and by a gate prefabrication technique, an oxide layer of an element isolation region is formed in a self-alignment manner using the first layer of the gate electrode as a mask, impurities for a transistor channel control are doped by ion implantation via the first layer of the gate electrode and the gate oxide film, and the doped impurities are activated by a heating step, whereby an impurity profile at the transistor channel portion is precisely formed.

Abstract: A device comprising: a layer of gate oxide on a surface of the semiconductor substrate; a gate electrode formed on the surface of the gate oxide, the gate electrode having a drain side; a p-well implanted within a semiconductor substrate under the gate electrode; an n-well implanted in the p-well on the drain side; an n+ source region in the p-well outside of the n-well; an n+ drain region within the substrate inside the n-well; and lightly doped regions extending respectively from the source and drain regions toward the gate electrode.

Abstract: A method for forming a Field Effect Transistor (FET) within a strain effect semiconductor layer is disclosed, whereby the source and drain of the FET are formed only in the strain effect silicon layer. The FET may be formed as a gate electrode of a p-channel type field effect transistor, and a gate electrode of a n-channel type field effect transistor on the silicon layer which has the strain effect through a gate insulating film. The sources and drains of p- and n-type diffusion layers are then formed in the silicon layer having the strain effect, on both sides of the gate electrode.

Abstract: There is provided a manufacturing method for a structure capable of realizing a power management semiconductor device and an analog semiconductor device in which a cost is low, a work period is short, and low voltage operation is possible, which have low power consumption and high drive capacity, and which is high function and high precision. The manufacturing method is a method of obtaining a P-type polycide structure as a laminate structure of a P-type polycrystalline silicon film and a high melting point metallic silicide film for respective gate electrodes of an NMOS transistor and a PMOS transistor as divided by a conductivity type thereof in a CMOS transistor. In addition, a resistor used for a voltage dividing circuit and a CR circuit is formed by using a polycrystalline silicon film as a layer different from the gate electrode, so that higher precision resistor can be provided.

Abstract: A method of forming retrograde n-wells and p-wells. A first mask is formed on the substrate and the n-well implants are carried out. Then the mask is thinned, and a deep p implant is carried out with the thinned n-well mask in place. This prevents Vt shifts in FETs formed in the n-well adjacent the nwell-pwell interface. The thinned mask is then removed, a p-well mask is put in place, and the remainder of the p-well implants are carried out.

Abstract: A method for forming a transistor of a semiconductor device, including the step of forming channel layers of a first and a second conductive types, performing high temperature thermal process to form stabilized channel layers and forming an epitaxial channel structure having a super-steep-retrograde &dgr;-doped layer by growing undoped silicon epitaxial layers, treating the entire surface of the resulting structure with hydrogen, forming an epitaxial channel structure by growing undoped silicon epitaxial layers on the stabilized channel layers, forming gate insulating films and gate electrodes on the epitaxial channel structures, re-oxidizing the gate insulating films for repairing damaged portions of the gate insulating films; and forming a source/drain region and performing a low temperature thermal process.

Abstract: An object of the invention is to suppress degradation of the effective isolation width between a well and a diffusion layer caused by impurity ion implantation for forming the well performed at a predetermined incident angle. A well is formed by performing impurity ion implantation twice: first impurity ion implantation from a first direction at predetermined incident angle, acceleration voltage and dose; and second impurity ion implantation from a second direction different from the first direction by 180 degrees in a plan view at the same incident angle, acceleration voltage and dose as those in the first impurity ion implantation.

Abstract: A power switching transistor for a fluid ejection device includes forming a first diffused region and doping the first diffused region with a first dopant. A first portion of the first diffused region is doped with a second dopant. The first portion of the first diffused region has a greater impurity concentration than at least a second portion of the first diffused region.

Abstract: The present invention provides a semiconductor device (e.g., MOSFET) having a channel above the surface of the wafer containing a well and a junction. The elevated channel may be selectively epitaxially grown and enables higher mobility, thereby enabling a higher current flow at a lower voltage through the device. The process flow of the invention provides for the implantation and thermal processing of the wells and junctions prior to the growth of a channel or the deposition of a gate stack. By implanting and annealing the wells and junctions prior to the formation of the channel and gate, a greater variety of materials are available for the channel and gate, e.g., undoped materials may be used to form the channel, metal oxides and similar materials with large dielectrics may be used to form a gate stack, and barrier metals and pure metals (copper, tungsten, etc.) may be used as gate electrodes.

Abstract: Structures for providing devices that include resistive paths specifically designed to provide a predetermined resistance between the bulk material of the device and a well tie contact. By providing a resistive path, an equivalent RC circuit is introduced to the device that allows the bulk material potential to track the gate potential, thereby advantageously lowering the threshold voltage as the device turns on and raising the threshold voltage as the device turns off. In addition, the introduction of the resistive path also allows the bulk material potential to be controlled and stabilize at an equilibrium potential between switching events.

Abstract: A CMOS transistor is formed on a single crystal silicon substrate. Active regions are formed on the substrate, including an nMOST active region and a pMOST active region. An epitaxial layer of undoped silicon is formed over the active regions. Out-diffusion from the underlying active regions produces dopant densities within the epitaxial layer one, or more, orders of magnitude lower than dopant densities within the underlying active regions. In a preferred embodiment, the epitaxial layer is counter doped by implanting ions of the opposite type to those within the underlying active region. Counter doping further reduces the dopant density, to reduce the threshold voltage further.

Abstract: There is disclosed a method of forming an isolation film in a semiconductor device, the method including the steps of: forming a silicon oxide film and a silicon nitride film in that order on a silicon substrate, using a resist pattern as a mask, etching the silicon nitride film and silicon oxide film, and forming trenches in the substrate. In the substrate, the respective trenches form a region in which isolation films are to be formed, and the region between the trenches forms an active region. In this case, each dimension is set so that a ratio W/t of width W to thickness t of the patterned silicon nitride film is 3.8 or more. Subsequently, by removing the resist pattern, subsequently using the silicon nitride film as the mask, and performing thermal oxidation at a temperature of 1050° C. to 1150° C. in an oxygen atmosphere, an isolation film is formed in the trench.

Abstract: A RESURF LDMOS transistor (64) includes a RESURF region (42) that is self-aligned to a LOCOS field oxide region (44). The self-alignment produces a stable breakdown voltage BVdss by eliminating degradation associated with geometric misalignment and process tolerance variation.

Abstract: Embodiments include a semiconductor device including a well structure such that well areas can be formed with a higher density of integration and a plurality of high-voltage endurable transistors can be driven independently of one another with different voltages, and a method of manufacturing the semiconductor device. The semiconductor device may include a triple well comprising a first well formed in a silicon substrate and having a first conductivity type (P-type), a second well formed in adjacent relation to the first well and having a second conductivity type (N-type), and a third well formed in the second well and having the first conductivity type (P-type). A high-voltage endurable MOSFET is provided in each of the wells. Each MOSFET has an offset area in the corresponding well around a gate insulating layer. The offset area is formed of a low-density impurity layer which is provided under an offset LOCOS layer on the silicon substrate.

Abstract: Method for fabricating a polycide dual gate in a semiconductor device fabricates a dual gate having polycide gate electrodes. The polycide can be a cobalt polycide, for example. The method can include forming polysilicon pattern layers on a first and a second regions of a semiconductor substrate, forming a blocking layer to expose top surfaces of the polysilicon pattern layers and mask the substrate, and forming a metal layer on an entire surface and then is annealed to form a gate electrode having a stack of the polysilicon pattern layer under a silicide layer. Impurity ions of opposite conductivities in the first and second regions can be respectively deposited and diffused to form source/drain regions in surfaces of the substrate on both sides of the gate electrode. The implanted impurity ions can further implant ions in the silicide/polysilicon pattern layer gate to reduce fabrication steps or simplify the fabrication process.

Abstract: A semiconductor device and method of manufacturing the same are provided. A trench is formed in a semiconductor substrate. A thin oxide liner is preferably formed on surfaces of the trench. After formation of the oxide liner, first regions of the semiconductor substrate are masked, leaving second regions thereof exposed. N-type devices are to be formed in the first regions and p-type devices are to be formed in the second regions. N-type ions may then be implanted into sidewalls of the trenches in the second regions. The mask is stripped and formation of the semiconductor device may be carried out in a conventional manner. The n-type ions are preferably only implanted into sidewalls where PMOSFETs are formed.

Abstract: A buried channel PMOS transistor for analog applications is integrated into a digital CMOS process. A third well region (105) is formed by implanting a region in the semiconductor substrate with all the n-type and p-type implants used to form the n-well and p-well regions for the digital CMOS process. A gate dielectric layer (50) and gate layer (109) are formed above the third well (105) and comprise the gate stack of the buried channel PMOS transistor. The implants used to form the drain extension regions and the source and drain regions of the CMOS transistors are used to complete the buried channel PMOS transistor.

Abstract: The present invention provides a semiconductor device, formed on a semiconductor wafer, comprising a tub, first and second active areas, and an interconnect. In one aspect of the present invention, the tub is formed in the substrate of the semiconductor wafer and first and second active areas are in contact with the tub. In one advantageous embodiment, the interconnect is formed in the tub and is in electrical contact with the first and second active areas. The interconnect extends from the first active area to the second active area to electrically connect the first and second active areas.