Abstract: An electronic component includes a high voltage switching transistor encased in a package. The high voltage switching transistor comprises a source electrode, a gate electrode, and a drain electrode all on a first side of the high voltage switching transistor. The source electrode is electrically connected to a conducting structural portion of the package. Assemblies using the abovementioned transistor with another transistor can be formed, where the source of one transistor can be electrically connected to a conducting structural portion of a package containing the transistor and a drain of the second transistor is electrically connected to the second conductive structural portion of a package that houses the second transistor. Alternatively, the source of the second transistor is electrically isolated from its conductive structural portion, and the drain of the second transistor is electrically isolated from its conductive structural portion.

Abstract: There are disclosed herein various implementations of composite semiconductor devices with active oscillation control. In one exemplary implementation, a normally OFF composite semiconductor device comprises a normally ON III-nitride power transistor and a low voltage (LV) device cascoded with the normally ON III-nitride power transistor to form the normally OFF composite semiconductor device. The LV device may be configured to include one or both of a reduced output resistance due to, for example, a modified body implant and a reduced transconductance due to, for example, a modified oxide thickness to cause a gain of the composite semiconductor device to be less than approximately 10,000.

Abstract: An integrated circuit device includes a substrate having adjacent first and second regions, and a device isolation structure in the substrate between the first and second regions. The first and second regions of the substrate may respectively include transistors configured to be driven at different operational voltages, and the device isolation structure may electrically separates the transistors of the first region from the transistors of the second region. The device isolation structure includes outer portions immediately adjacent to the first and second regions and an inner portion therebetween. The outer portions of the device isolation structure comprise a material having an etching selectivity with respect to that of the inner portion. Related devices and fabrication methods are also discussed.

Abstract: A tantalum alloy layer is employed as a work function metal for field effect transistors. The tantalum alloy layer can be selected from TaC, TaAl, and TaAlC. When used in combination with a metallic nitride layer, the tantalum alloy layer and the metallic nitride layer provides two work function values that differ by 300 mV˜500 mV, thereby enabling multiple field effect transistors having different threshold voltages. The tantalum alloy layer can be in contact with a first gate dielectric in a first gate, and the metallic nitride layer can be in contact with a second gate dielectric having a same composition and thickness as the first gate dielectric and located in a second gate.

Abstract: An SOI substrate, a semiconductor device, and a method of backgate work function tuning. The substrate and the device have a plurality of metal backgate regions wherein at least two regions have different work functions. The method includes forming a mask on a substrate and implanting a metal backgate interposed between a buried oxide and bulk regions of the substrate thereby producing at least two metal backgate regions having different doses of impurity and different work functions. The work function regions can be aligned such that each transistor has different threshold voltage. When a top gate electrode serves as the mask, a metal backgate with a first work function under the channel region and a second work function under the source/drain regions is formed. The implant can be tilted to shift the work function regions relative to the mask.

Abstract: Disclosed are embodiments of an integrated circuit structure that incorporates at least two field effect transistors (FETs) that have the same conductivity type and essentially identical semiconductor bodies (i.e., the same semiconductor material and, thereby the same conduction and valence band energies, the same source, drain, and channel dopant profiles, the same channel widths and lengths, etc.). However, due to different gate structures with different effective work functions, at least one of which is between the conduction and valence band energies of the semiconductor bodies, these FETs have selectively different threshold voltages, which are independent of process variables. Furthermore, through the use of different high-k dielectric materials and/or metal gate conductor materials, the embodiments allow threshold voltage differences of less than 700 mV to be achieved so that the integrated circuit structure can function at power supply voltages below 1.0V.

Abstract: A semiconductor device can output a reference voltage for an arbitrary potential and can detect the voltage of each cell in a battery including multiple cells very precisely. The device includes a depletion-type MOSFET 21 and an enhancement type MOSFET 22, and has a floating structure that isolates depletion-type MOSFET 21 and enhancement type MOSFET 22 from a ground terminal. The depletion-type MOSFET 21 and enhancement type MOSFET 22 are connected in series to each other, wherein the depletion-type MOSFET 21 is connected to high-potential-side terminal and the enhancement type MOSFET 22 is connected to low-potential-side terminal. The semiconductor device having the configuration described above is disposed in a voltage detecting circuit section in a control IC for a battery including multiple cells.

Abstract: A structure and method for forming a dual metal fill and dual threshold voltage for replacement gate metal devices is disclosed. A selective deposition process involving titanium and aluminum is used to allow formation of two adjacent transistors with different fill metals and different workfunction metals, enabling different threshold voltages in the adjacent transistors.

Abstract: A field-effect transistor includes a first gate, a second gate held at a substantially fixed potential in a cascode configuration, and a semiconductor channel. The semiconductor channel has an enhancement mode portion and a depletion mode portion. The enhancement mode portion is gated to be turned on and off by the first gate, and has been modified to operate in enhancement mode. The depletion mode portion is gated by the second gate, and has been modified to operate in depletion mode and that is operative to shield the first gate from voltage stress.

Abstract: A method forms a metal high dielectric constant (MHK) transistor and includes: providing a MHK stack disposed on a substrate, the MHK stack including a first layer of high dielectric constant material, a second overlying layer, and a third overlying layer, selectively removing only the second and third layers, without removing the first layer, to form an upstanding portion of a MHK gate structure; forming a first sidewall layer on sidewalls of the upstanding portion of the MHK gate structure; forming a second sidewall layer on sidewalls of the first sidewall layer; removing a portion of the first layer to form exposed surfaces; forming an offset spacer layer over the second sidewall layer and over the first layer, and forming in the substrate extensions that underlie the first and second sidewall layers and that extend under a portion but not all of the upstanding portion of the MHK gate structure.

Abstract: A semiconductor structure comprising an SRAM/inverter cell and a method for forming the same are provided, wherein the SRAM/inverter cell has an improved write margin. The SRAM/inverter cell includes a pull-up PMOS device comprising a gate dielectric over the semiconductor substrate, a gate electrode on the gate dielectric wherein the gate electrode comprises a p-type impurity and an n-type impurity, and a stressor formed in a source/drain region. The device drive current of the pull-up PMOS device is reduced due to the counter-doping of the gate electrode.

Abstract: A method includes forming a first gate stack over a portion of a fin, forming a dummy gate stack over the fin, growing an epitaxial material from exposed portions of the fin, forming a layer of dielectric material over the epitaxial material, the first gate stack, and the dummy gate stack, performing a planarizing process that removes portions of the layer of dielectric material, the first gate stack, and the dummy gate stack, pattering a first mask over portions of the layer of dielectric material and the dummy gate stack, forming a silicide material on exposed portions of the first gate stack, removing the first mask, pattering a second mask over portions of the layer of dielectric material and the first gate stack, removing a polysilicon portion of the dummy gate stack to define a cavity, removing the second mask, and forming a second gate stack in the cavity.

Abstract: An advanced transistor with punch through suppression includes a gate with length Lg, a well doped to have a first concentration of a dopant, and a screening region positioned under the gate and having a second concentration of dopant. The second concentration of dopant may be greater than 5×1018 dopant atoms per cm3. At least one punch through suppression region is disposed under the gate between the screening region and the well. The punch through suppression region has a third concentration of a dopant intermediate between the first concentration and the second concentration of dopant. A bias voltage may be applied to the well region to adjust a threshold voltage of the transistor.

Abstract: A semiconductor device includes a compound semiconductor layer provided over a substrate, a plurality of source electrodes and a plurality of drain electrodes provided over the compound semiconductor layer, a plurality of first vias each of which is configured to pass through the compound semiconductor layer and be coupled to a corresponding one of the plurality of source electrodes, a plurality of second vias each of which is configured to pass through the compound semiconductor layer and be coupled to a corresponding one of the plurality of drain electrodes, a common source wiring line configured to be coupled to the plurality of first vias and be buried in the substrate, and a common drain wiring line configured to be coupled to the plurality of second vias and be buried in the substrate.

Abstract: When forming sophisticated gate electrode structures of transistor elements of different type, the threshold adjusting channel semiconductor alloy may be provided prior to forming isolation structures, thereby achieving superior uniformity of the threshold adjusting material. Consequently, threshold variability on a local and global scale of P-channel transistors may be significantly reduced.

Abstract: The invention describes in detail the structure of a CMOS image sensor pixel that senses color of impinging light without having absorbing filters placed on its surface. The color sensing is accomplished by having a vertical stack of three-charge detection nodes placed in the silicon bulk, which collect electrons depending on the depth of their generation. The small charge detection node capacitance and thus high sensitivity with low noise is achieved by using fully depleted, potential well forming, buried layers instead of undepleted junction electrodes. Two embodiments of contacting the buried layers without substantially increasing the node capacitances are presented.

Abstract: A formation method of an element isolation film according to which a high-voltage transistor with an excellent characteristic can be formed is provided. On a substrate, a gate oxide film is previously formed. A CMP stopper film is formed thereon, and thereafter, a gate oxide film and a CMP stopper film are etched. The semiconductor substrate is etched to form a trench. Further, before the trench is filled with a field insulating film, a liner insulating film is formed at a trench interior wall, and a concave portion at the side surface of the gate oxide film under the CMP stopper film is filled with the liner insulating film. In this manner, formation of void in the element isolation film laterally positioned with respect to the gate oxide film can be prevented.

Abstract: Band edge engineered Vt offset devices, design structures for band edge engineered Vt offset devices and methods of fabricating such structures is provided herein. The structure includes a first FET having a channel of a first compound semiconductor of first atomic proportions resulting in a first band structure and a first type. The structure further includes a second FET having a channel of a second compound semiconductor of second atomic proportions resulting in a second band structure and a first type. The first compound semiconductor is different from the second compound semiconductor such that the first FET has a first band structure different from second band structure, giving rise to a threshold voltage different from that of the second FET.

Abstract: Gate electrodes are formed in a high speed transistor forming region, a low leakage transistor forming region, and a medium voltage transistor forming region, respectively. Thereafter, a photoresist film covering the medium voltage transistor forming region is formed. Then, ions of an impurity are implanted into a semiconductor substrate while using the photoresist film and the gate electrodes as a mask, and p-type pocket regions, extension regions, and impurity regions are thereby formed. Subsequently, another photoresist film covering the high speed transistor forming region is formed. Then, ions of an impurity are implanted into the semiconductor substrate while using the other photoresist film and the gate electrodes as a mask, and impurity regions and extension regions are thereby formed.

Abstract: A method of manufacturing a semiconductor device involves process for forming gate insulating films of different thickness on a semiconductor substrate, depositing films that constitute a gate electrode, removing the gate insulating films having different thickness formed on an impurity diffusion region surface of a transistor including the gate electrode, and doping impurities into a portion where the gate insulating film is removed.

Abstract: An electronic component includes a high voltage switching transistor encased in a package. The high voltage switching transistor comprises a source electrode, a gate electrode, and a drain electrode all on a first side of the high voltage switching transistor. The source electrode is electrically connected to a conducting structural portion of the package. Assemblies using the abovementioned transistor with another transistor can be formed, where the source of one transistor can be electrically connected to a conducting structural portion of a package containing the transistor and a drain of the second transistor is electrically connected to the second conductive structural portion of a package that houses the second transistor. Alternatively, the source of the second transistor is electrically isolated from its conductive structural portion, and the drain of the second transistor is electrically isolated from its conductive structural portion.

Abstract: An integrated circuit (IC) includes a substrate having a top semiconductor surface including at least one MOS device including a source and a drain region spaced apart to define a channel region. A SiON gate dielectric layer that has a plurality of different N concentration portions is formed on the top semiconductor surface. A gate electrode is on the SiON layer. The plurality of different N concentration portions include (i) a bottom portion extending to the semiconductor interface having an average N concentration of <2 atomic %, (ii) a bulk portion having an average N concentration >10 atomic %, and (iii) a top portion on the bulk portion extending to a gate electrode interface having an average N concentration that is ?2 atomic % less than a peak N concentration of the bulk portion.

Abstract: A multi-gate semiconductor device and method for forming the same. A multi-gate semiconductor device is formed including a first fin of a first transistor formed on a semiconductor substrate having a first dopant type. The first transistor has a doped channel region of the first dopant type. The device also includes a second fin of a second transistor formed on the first dopant type semiconductor substrate. The second transistor has a doped channel region of a second dopant type. The device further includes a gate electrode layer of the second dopant type formed over the channel region of the first fin and a gate electrode layer of the first dopant type formed over the channel region of the second fin.

Abstract: A semiconductor substrate according to one embodiment includes: a first transistor having a first gate insulating film formed on a semiconductor substrate, a first gate electrode formed on the first gate insulating film and a first sidewall formed on a side face of the first gate electrode, the first gate insulating film comprising a high-dielectric constant material as a base material, a part of the first sidewall contacting with the first gate insulating film and containing Si and N; and a second transistor having a second gate insulating film formed on the semiconductor substrate, a second gate electrode formed on the second gate insulating film and a second sidewall formed on a side face of the second gate electrode so as to contact with the second gate insulating film, the second gate insulating film comprising a high-dielectric constant material as a base material, a part of the second sidewall contacting with the second gate insulating film and containing Si and N, wherein at least one of an abundance

Abstract: A semiconductor device has a semiconductor substrate in which first and second wells are formed. The substrate and wells are of the same conductivity type, but the second well has a higher impurity concentration than the first well. High-voltage MOS transistors are formed in the first well, and a low-voltage MOS transistor is formed in the second well. The high-voltage MOS transistors include a first transistor having a gate oxide layer with a first thickness and a second transistor having a gate oxide layer with a second thickness less than the first thickness. The low-voltage MOS transistor has a third gate oxide layer with a third thickness less than the first thickness. The second high-voltage MOS transistor provides efficient current conduction.

Abstract: Semiconductor structures are disclosed that include at least one FET gate stack located on a semiconductor substrate. The at least one FET gate stack includes source and drain extension regions located within the semiconductor substrate. A device channel is also present between the source and drain extension regions and beneath the at least one gate stack. Embedded stressor elements are located on opposite sides of the at least one FET gate stack and within the semiconductor substrate. Each stressor element includes a lower layer of a first epitaxy doped semiconductor material having a lattice constant that is different from a lattice constant of the semiconductor substrate and imparts a strain in the device channel, and an upper layer of a second epitaxy doped semiconductor material. At least one monolayer of dopant is located within the upper layer of each of the embedded stressor elements.

Abstract: A power module comprises: first and second terminals; first and second switching elements having a first electrode and a second electrode which is connected to the second terminal; first and second wirings respectively connecting the first electrodes of the first and second switching elements to the first terminal; and a third wiring directly connecting the first electrode of the first switching element to the first electrode of the second switching element, wherein parasitic inductances of the first and second wiring are different or switching characteristics of the first and second switching elements are different.

Abstract: An advanced transistor with punch through suppression includes a gate with length Lg, a well doped to have a first concentration of a dopant, and a screening region positioned under the gate and having a second concentration of dopant. The second concentration of dopant may be greater than 5×1018 dopant atoms per cm3. At least one punch through suppression region is disposed under the gate between the screening region and the well. The punch through suppression region has a third concentration of a dopant intermediate between the first concentration and the second concentration of dopant. A bias voltage may be applied to the well region to adjust a threshold voltage of the transistor.

Abstract: A semiconductor device according to the invention includes: a first region on a semiconductor substrate, in which a first transistor is formed, the first transistor including first gate insulating film 4 containing a high dielectric constant material and first metal gate electrode 5 formed on first gate insulating film 4; a second region adjacent to the first region on the semiconductor substrate, in which a second transistor is formed, the second transistor including second gate insulating film 4 and second metal gate electrode 12 formed on the second gate insulating film, a layered structure of electrode materials of the second transistor being different from a layered structure of electrode materials of the first transistor; and a first and a second line, the lines being of different potentials, wherein a border between the first and the second region overlaps with at most only the first or the second line.

Abstract: A semiconductor memory device and method of manufacturing the same, the device including string structures, the string structures including two or more adjacent string selection transistors connected in series to each other in a first direction and being spaced apart from one another in a second direction intersecting the first direction, the two or more string selection transistors having different threshold voltages; string selection lines, the string selection lines connecting the adjacent string selection transistors of the string structures in the second direction; and a bit line electrically connecting two or more adjacent string structures, wherein a device isolation layer between the adjacent string selection transistors in the second direction has recessed regions, and profiles of the recessed regions on respective sides of the string selection transistors are different from each other.

Abstract: In accordance with an embodiment, a semiconductor device includes an SRAM cell on a substrate. The SRAM cell includes: first and second load transistors each having an n-type source region and a p-type drain region, first and second driver transistors each having a p-type source region and an n-type drain region, and first and second transfer transistors each having an n-type source region and a n-type drain region. The n-type source regions of the first and second load transistors, the n-type drain regions of the first and second driver transistors, and the n-type source regions and the n-type drain regions of the first and second transfer transistors are located in a region other than a region present between any two of the p-type drain regions of the first and second load transistors and the p-type source regions of the first and second driver transistors.

Abstract: A semiconductor device includes a semiconductor substrate including a first region having a cell region and a second region having a peripheral circuit region, first transistors on the semiconductor substrate, a first protective layer covering the first transistors, a first insulation layer on the first protective layer, a semiconductor pattern on the first insulation layer in the first region, second transistors on the semiconductor pattern, a second protective layer covering the second transistors, the second protective layer having a thickness greater than that of the first protective layer, and a second insulation layer on the second protective layer and the first insulation layer of the second region.

Abstract: A semiconductor device includes a semiconductor substrate having a first portion and a second portion and a first transistor of a first type formed in the first portion of the substrate, the first transistor being operable at a first voltage, and the first transistor including a doped channel region of a second type opposite of the first type. The semiconductor device also includes a second transistor of the second type formed in the second portion of the substrate, the second transistor being operable at a second voltage greater than the first voltage, the second transistor including an extended doped feature of the second type. Further, the semiconductor device includes a well of the first type in the semiconductor substrate under a gate of the second transistor, wherein the well does not extend directly under the extended doped feature and the extended doped feature does not extend directly under the well.

Abstract: In a semiconductor device and a method of making the same, a first transistor has a gate stack comprising an underlying layer formed of a first material and an overlying layer formed of a second material. A second transistor has a gate stack comprising an underlying layer formed of a third material and an overlying layer formed of the second material. A third transistor has a gate stack comprising an underlying layer formed of the first material and an overlying layer formed of a fourth material. A fourth transistor has a gate stack comprising an underlying layer formed of the third material and an overlying material formed of the fourth material. Each of the first through fourth materials has a respectively different work function, so that each of the first through fourth transistors has a respectively different threshold voltage.

Abstract: A semiconductor device includes a first MIS transistor and a second MIS transistor. The first MIS transistor includes first offset sidewalls formed on side surfaces in a gate width direction of a first gate electrode, second offset sidewalls formed on side surfaces in a gate length direction and the side surfaces of the gate width direction of the first gate electrode with the first offset sidewalls being interposed between the second offset sidewalls and the first gate electrode, and first extension regions. The second MIS transistor includes third offset sidewalls formed on side surfaces in a gate length direction and a gate width direction of a second gate electrode, fourth offset sidewalls formed on the side surfaces in the gate length and width directions of the second gate electrode with the third offset sidewalls being interposed between the fourth offset sidewalls and the second gate electrode, and second extension regions.

Abstract: A technique is provided which allows a chip mounted by wire bonding and a chip mounted by bump electrodes to share a manufacturing process. Both in a case where a chip is electrically coupled to an external circuit by bump electrodes and a case where the chip is electrically coupled to the external circuit by bonding wires, a bump coupling part and a bonding pad are both provided in a single uppermost wiring layer. When the bump electrodes are used, an opening is provided in an insulating film on the bump coupling part and a surface of the bonding pad is covered with the insulating film. On the other hand, when the bonding wires are used, an opening is provided in an insulating film on the bonding pad and a surface of the bump coupling part is covered with the insulating film.

Abstract: A semiconductor device includes a semiconductor substrate including a first driving transistor region having a first driving transistor disposed therein and a second driving transistor region having a second driving transistor disposed therein, wherein the second driving transistor is driven at a lower voltage than the first driving transistor, a first gate insulating layer formed at edges of the second driving transistor region, and a second gate insulating layer formed at a center of the second driving transistor region, wherein the first gate insulating layer is thicker than the second gate insulating layer.

Abstract: Transistors are provided including first and second source/drain regions, a channel region and a gate stack having a first gate dielectric over a substrate, the first gate dielectric having a dielectric constant higher than a dielectric constant of silicon dioxide, and a metal material in contact with the first gate dielectric, the metal material being doped with an inert element. Integrated circuits including the transistors and methods of forming the transistors are also provided.

Abstract: In one embodiment, a semiconductor device includes a substrate; a gate insulating film; first trenches in a cell array region; first embedded insulating films in the first trenches; second trenches in a peripheral circuit region; second embedded insulating films in the second trenches; a third trench in an isolation region; a third embedded insulating film in the third trench; gate structures; and inter-gate insulating films between the gate structures covering the first, second and third embedded insulating films. An upper surface of the third embedded insulating film covered with the inter-gate insulating film is substantially flat. Upper surfaces of the first, second, and third embedded insulating films are higher than an upper surface of the gate insulating film. The upper surfaces of the first and third embedded insulating films are lower than the upper surfaces of the second embedded insulating films.

Abstract: When MOS transistors having a plurality of threshold voltages in which a source and a drain form a symmetrical structure are mounted on the same substrate, electrically-symmetrical characteristics is provided with respect to an exchange of the source and the drain in each MOS transistor. A MOS transistor having a large threshold voltage is provided with a halo diffusion region, and halo implantation is not performed on a MOS transistor having a small threshold voltage.

Abstract: Disclosed are high linearity CMOS-based devices capable of passing large signal and quiescent power amplifier current for switching radio frequency (RF) signals, and methods for biasing such devices. In certain RF devices such as mobile phones, providing different amplification modes can yield performance advantages. For example, a capability to transmit at low and high power modes typically results in an extended battery life, since the high power mode can be activated only when needed. Switching between such amplification modes can be facilitated by one or more switches formed in an integrated circuit and configured to route RF signal to different amplification paths. In certain embodiments, such RF switches can be formed as CMOS devices, and can be based on triple-well structures.

Abstract: A semiconductor device and a method for manufacturing the same are disclosed. The method for manufacturing the semiconductor device forms a recess gate region on a semiconductor substrate, forms an isolation layer isolated from the recess gate region using a high-temperature thermal process, and guarantees a larger channel region by filling the isolation layer with a gate electrode material, so that a cell current is increased and on/off characteristics of a transistor are improved.

Abstract: An electronic device comprising a field-effect transistor having an inter digitated structure suitable for high-frequency power applications, and having multiple threshold voltages that are provided in different regions of each a segment of the interdigitated structure. This leads to a dramatic improvement in linearity over a large power range in the back-off region under class AB signal operation.

Abstract: In sophisticated semiconductor devices, different threshold voltage levels for transistors may be set in an early manufacturing stage, i.e., prior to patterning the gate electrode structures, by using multiple diffusion processes and/or gate dielectric materials. In this manner, substantially the same gate layer stacks, i.e., the same electrode materials and the same dielectric cap materials, may be used, thereby providing superior patterning uniformity when applying sophisticated etch strategies.

Abstract: The invention concerns a conducting layer having a thickness of between 1 and 5 atoms, an insulated gate being formed over a part of the conducting layer.

Abstract: When forming the strain-inducing semiconductor alloy in one type of transistor of a sophisticated semiconductor device, superior thickness uniformity of a dielectric cap material of the gate electrode structures may be achieved by forming encapsulating spacer elements on each gate electrode structure and providing an additional hard mask material. Consequently, in particular, in sophisticated replacement gate approaches, the dielectric cap material may be efficiently removed in a later manufacturing stage, thereby avoiding any irregularities upon replacing the semiconductor material by an electrode metal.

Abstract: An exemplary integrated circuit module includes a first transistor and a second transistor. The first transistor has a first channel length and a first threshold voltage. The second transistor is electrically coupled to the first transistor and has a second channel length and a second threshold voltage. The second channel length is greater than the first channel length, the absolute value of the second threshold voltage is smaller than the absolute value of the first threshold voltage, and the first transistor and the second transistor have a same threshold voltage implant concentration. Moreover, a manufacturing method of such integrated circuit module, and an application of such integrated circuit module to computer aided design of logic circuit also are provided.

Abstract: Band edge engineered Vt offset devices, design structures for band edge engineered Vt offset devices and methods of fabricating such structures is provided herein. The structure includes a first FET having a channel of a first compound semiconductor of first atomic proportions resulting in a first band structure and a first type. The structure further includes a second FET having a channel of a second compound semiconductor of second atomic proportions resulting in a second band structure and a first type. The first compound semiconductor is different from the second compound semiconductor such that the first FET has a first band structure different from second band structure, giving rise to a threshold voltage different from that of the second FET.

Abstract: An integrated circuit, in which a minimum gate length of low-noise NMOS transistors is less than twice a minimum gate length of logic NMOS transistors, is formed by: forming gates of the low-noise NMOS transistors concurrently with gates of the logic NMOS transistors, forming a low-noise NMDD implant mask which exposes the low-noise NMOS transistors and covers the logic NMOS transistors and logic PMOS transistors, ion implanting n-type NMDD dopants and fluorine into the low-noise NMOS transistors and limiting p-type halo dopants to less than 20 percent of a corresponding logic NMOS halo dose, removing the low-noise NMDD implant mask, forming a logic NMDD implant mask which exposes the logic NMOS transistors and covers the low-noise NMOS transistors and logic PMOS transistors, ion implanting n-type NMDD dopants and p-type halo dopants, but not implanting fluorine, into the logic NMOS transistors, and removing the logic NMDD implant mask.

Abstract: At least three metal-oxide semiconductor transistors with different threshold voltages are formed in and above corresponding first, second and third parts of a semiconductor substrate. The second transistor has a lower threshold voltage than the second transistor, and the third transistor has a lower threshold voltage than the second transistor. The gate oxide layers for the three transistors are formed as follows: a first oxide layer having a first thickness is formed above the first, second and third parts. The first oxide layer above the second part is etched and a second oxide layer having a second thickness smaller than the first thickness is formed. The first oxide layer above the third part is etched and a third oxide layer having a third thickness smaller than the second thickness is formed. The second and the third oxide layers are then nitrided to form first and second oxy-nitride layers.