Abstract: An improved structure of heterojunction field effect transistor (HFET) and a fabrication method thereof are disclosed. The improved HFET structure comprises sequentially a substrate, a channel layer, a spacing layer, a carrier supply layer, a Schottky layer, a Schottky capping layer formed by a higher energy gap material, a tunneling layer formed by a lower energy gap material, a first etching stop layer, and a first n type doped layer.

Abstract: A semiconductor device includes: an epitaxial substrate formed by stacking a plurality of kinds of semiconductors over one semiconductor substrate by epitaxial growth; a field effect transistor of a first conductivity type formed in a first region; a field effect transistor of a second conductivity type formed in a second region; and a protective element formed in a third region. The protective element includes: a first stacking structure formed by etching the epitaxial substrate by vertical etching that proceeds in a stacking thickness direction; and a second stacking structure formed by etching the epitaxial substrate by vertical etching that proceeds in a stacking thickness direction. The protective element has two PN junctions on a current path formed between an upper end of the first stacking structure and an upper end of the second stacking structure via a base part of the first stacking structure and the second stacking structure.

Abstract: The disclosure relates to a complementary junction field effect transistor (c-JFET) and its gate-last fabrication method. The method of fabricating a semiconductor device includes: forming a dummy gate on a first conductivity type wafer, forming sidewall spacers on opposite sides of the dummy gate, forming a source and a drain regions on the opposite sides of the dummy gate, removing the dummy gate, forming a first semiconductor region of a second conductivity type in an opening exposed through the removing the dummy gate, and forming a gate electrode in the opening.

Abstract: Transistors, methods of manufacturing thereof, and image sensor circuits are disclosed. In one embodiment, a transistor includes a buried channel disposed in a workpiece, a gate dielectric disposed over the buried channel, and a gate layer disposed over the gate dielectric. The gate layer comprises an I shape in a top view of the transistor.

Abstract: According to one embodiment, a nitride semiconductor device includes a first semiconductor, a second semiconductor layer, a third semiconductor layer, a fourth semiconductor layer, a first electrode, a second electrode and a third electrode. The first, second and fourth semiconductor layers include a nitride semiconductor. The second semiconductor layer is provided on the first semiconductor layer, has a band gap not less than that of the first semiconductor layer. The third semiconductor layer is provided on the second semiconductor layer. The third semiconductor layer is GaN. The fourth semiconductor layer is provided on the third semiconductor layer to have an interspace on a part of the third semiconductor layer, has a band gap not less than that of the second semiconductor layer. The first electrode is provided on a portion of the third semiconductor layer. The fourth semiconductor layer is not provided on the portion.

Abstract: A method for fabricating an electronic device includes providing an engineered substrate structure comprising a III-nitride seed layer, forming GaN-based functional layers coupled to the III-nitride seed layer, and forming a first electrode structure electrically coupled to at least a portion of the GaN-based functional layers. The method also includes joining a carrier substrate opposing the GaN-based functional layers and removing at least a portion of the engineered substrate structure. The method further includes forming a second electrode structure electrically coupled to at least another portion of the GaN-based functional layers and removing the carrier substrate.

Abstract: A method includes depositing a dummy fill material over exposed portions of a substrate and a gate stack disposed on the substrate, removing portions of the dummy fill material to expose portions of the substrate, forming a layer of spacer material over the exposed portions of the substrate, the dummy fill material and the gate stack, removing portions of the layer of spacer material to expose portions of the substrate and the dummy fill material, depositing a dielectric layer over the exposed portions of the spacer material, the substrate, and the gate stack, removing portions of the dielectric layer to expose portions of the spacer material, removing exposed portions of the spacer material to expose portions of the substrate and define at least one cavity in the dielectric layer, and depositing a conductive material in the at least one cavity.

Abstract: A semiconductor device includes a semiconductor substrate configured to include a channel, first and second ohmic contacts supported by the semiconductor substrate, in ohmic contact with the semiconductor substrate, and spaced from one another for current flow between the first and second ohmic contacts through the channel, and first and second dielectric layers supported by the semiconductor substrate. At least one of the first and second ohmic contacts extends through respective openings in the first and second dielectric layers. The second dielectric layer is disposed between the first dielectric layer and a surface of the semiconductor substrate, and the second dielectric layer includes a wet etchable material having an etch selectivity to a dry etchant of the first dielectric layer.

Abstract: A device includes a buried well region and a first HVW region of the first conductivity, and an insulation region over the first HVW region. A drain region of the first conductivity type is disposed on a first side of the insulation region and in a top surface region of the first HVW region. A first well region and a second well region of a second conductivity type opposite the first conductivity type are on the second side of the insulation region. A second HVW region of the first conductivity type is disposed between the first and the second well regions, wherein the second HVW region is connected to the buried well region. A source region of the first conductivity type is in a top surface region of the second HVW region, wherein the source region, the drain region, and the buried well region form a JFET.

Abstract: A semiconductor device includes a III-nitride substrate and a first III-nitride epitaxial layer coupled to the III-nitride substrate and comprising a drift region, a channel region, and an extension region. The channel region is separated from the III-nitride substrate by the drift region. The channel region is characterized by a first width. The extension region is separated from the drift region by the channel region. The extension region is characterized by a second width less than the first width. The semiconductor device also includes a second III-nitride epitaxial layer coupled to a top surface of the extension region, a III-nitride gate structure coupled to a sidewall of the channel region and laterally self-aligned with respect to the extension region, and a gate metal structure in electrical contact with the III-nitride gate structure and laterally self-aligned with respect to the extension region.

Abstract: A semiconductor structure is fabricated with reduced gate capacitance by thinning of a gate electrode to provide a reduced thickness gate electrode. The gate electrode is thinned after forming a spacer layer adjoining the gate electrode. In addition, the height of the spacer layer may also be reduced. The spacer layer thus has an enhanced horizontal width desired for locating an intrinsic source/drain with respect to an extension region and in particular, an enhanced horizontal width relative to the spacer height. The reduced thickness gate electrode may be fully silicided to provide decreased gate resistance. A raised source/drain layer may be located upon the intrinsic source/drain region. The raised source/drain layer may have a top surface higher than the reduced thickness gate electrode. In addition, the raised source/drain layer may have a top surface higher than the reduced height spacer layer.

Abstract: The disclosure relates to a complementary junction field effect transistor (c-JFET) and its gate-last fabrication method. The method of fabricating a semiconductor device includes: forming a dummy gate on a first conductivity type wafer, forming sidewall spacers on opposite sides of the dummy gate, forming a source and a drain regions on the opposite sides of the dummy gate, removing the dummy gate, forming a first semiconductor region of a second conductivity type in an opening exposed through the removing the dummy gate, and forming a gate electrode in the opening.

Abstract: Disclosed is an HJFET 110 which comprises: a channel layer 12 composed of InyGa1-yN (0?y?1); a carrier supply layer 13 composed of AlxGa1-xN (0?x?1), the carrier supply layer 13 being provided over the channel layer 12 and including at least one p-type layer; and a source electrode 15S, a drain electrode 15D and a gate electrode 17 which are disposed facing the channel layer 12 through the p-type layer, and provided over the carrier supply layer 13. The following relational expression is satisfied: 5.6×1011x<NA×?×t [cm?2]<5.6×1013x, where x denotes an Al compositional ratio of said carrier supply layer, t denotes a thickness of said p-type layer, NA denotes an impurity concentration, and ? denotes an activation ratio.

Abstract: A method includes depositing a dummy fill material over exposed portions of a substrate and a gate stack disposed on the substrate, removing portions of the dummy fill material to expose portions of the substrate, forming a layer of spacer material over the exposed portions of the substrate, the dummy fill material and the gate stack, removing portions of the layer of spacer material to expose portions of the substrate and the dummy fill material, depositing a dielectric layer over the exposed portions of the spacer material, the substrate, and the gate stack, removing portions of the dielectric layer to expose portions of the spacer material, removing exposed portions of the spacer material to expose portions of the substrate and define at least one cavity in the dielectric layer, and depositing a conductive material in the at least one cavity.

Abstract: A stacked planar device and method for forming the same is shown that includes forming, on a substrate, a stack of layers having alternating sacrificial and channel layers, patterning the stack such that sides of the stack include exposed surfaces of the sacrificial and channel layers, forming a dummy gate structure over a region of the stack to establish a planar area, forming a dielectric layer around the dummy gate structure to cover areas adjacent to the planar area, removing the dummy gate structure to expose the stack, selectively etching the stack to remove the sacrificial layers from the channel layers in the planar area, and forming a gate conductor over and in between the channel layers to form a transistor device.

Abstract: A single chip wireless sensor comprises a microcontroller connected by a transmit/receive interface to a wireless antenna. The microcontroller is also connected to an 8 kB RAM, a USB interface, an RS232 interface, 64 kB flash memory, and a 32 kHz crystal. The device senses humidity and temperature, and a humidity sensor is connected by an 18 bit ?? A-to-D converter to the microcontroller and a temperature sensor is connected by a 12 bit SAR A-to-D converter to the microcontroller. The device is an integrated chip manufactured in a single process in which both the electronics and sensor components are manufactured using standard CMOS processing techniques, applied to achieve both electronic and sensing components in an integrated process.

Abstract: There is provided a low power memory device with JFET device structures. Specifically, a low power memory device is provided that includes a plurality memory cells having a memory element and a JFET access device electrically coupled to the memory element. The memory cells may be isolated using diffusion based isolation.

Abstract: A semiconductor device has a first MOS transistor formed on first active region of the first conductivity type, having first gate electrode structure, first source/drain regions, recesses formed in the first source/drain regions, and semiconductor buried regions buried and grown on the recesses for applying stress to the channel under the first gate electrode structure, and a second MOS transistor formed on second active region of the second conductivity type, having second gate electrode structure, second source/drain regions, and semiconductor epitaxial layers formed on the second source/drain regions without forming recesses and preferably applying stress to the channel under the second gate electrode structure. In a CMOS device, performance can be improved by utilizing stress and manufacture processes can be simplified.

Abstract: A junction field effect transistor having a drain and a source, each defined by regions of a first type of semiconductor interconnected by a channel, and in which a dopant profile at a side of the drain facing the channel is modified so as to provide a region of reduced doping compared to a body region of the drain. The region of reduced doping and the body region can be defined by the same mask and doping step, but the mask is shaped to provide a lesser amount and thus less depth of doping for the region of reduced doping.

Abstract: Embodiments of the present invention provide for the dissipation of heat from semiconductor-on-insulator (SOI) structures. In one embodiment, a method for fabricating an integrated circuit is disclosed. In a first step, active circuitry is formed in an active layer of a SOI wafer. In a second step, substrate material is removed from a substrate layer disposed on a back side of the SOI wafer. In a third step, insulator material is removed from the back side of the SOI wafer to form an excavated insulator region. In a fourth step, a thermal dissipation layer is deposited on said excavated insulator region. The thermal dissipation layer is thermally conductive and electrically insulating.

Abstract: A high voltage JFET has a deep well of a first type of conductivity made in a semiconductor substrate, a further well of an opposite second type of conductivity arranged in the deep well, a shallow well of a first type of conductivity arranged in the further well, a first contact region for source and a second contact region for drain arranged in the further well, a third contact region for gate arranged between the first contact region and the second contact region in the shallow well, a first distance between the first contact region and the third contact region being smaller than a second distance between the second contact region and the third contact region, and an electrical connection between the first contact region and the second contact region via at least one channel region present between the deep well and the shallow well in the further well.

Abstract: A semiconductor device includes: a first semiconductor layer including AlXGa1-XN (0?X?1); a second semiconductor layer provided on the first semiconductor layer, including AlYGa1-YN (0?Y?1, X<Y), and having a larger bandgap than the first semiconductor layer; a source electrode provided on the second semiconductor layer; a drain electrode provided on the second semiconductor layer; and a gate electrode provided on the second semiconductor layer between the source electrode and the drain electrode. A region of the second semiconductor layer below the gate electrode at a depth short of the first semiconductor layer is doped with atoms to be negatively charged in the second semiconductor layer.

Abstract: Disclosed are embodiments of a junction field effect transistor (JFET) structure with one or more P-type silicon germanium (SiGe) or silicon germanium carbide (SiGeC) gates (i.e., a SiGe or SiGeC based heterojunction JFET). The P-type SiGe or SiGeC gate(s) allow for a lower pinch off voltage (i.e., lower Voff) without increasing the on resistance (Ron). Specifically, SiGe or SiGeC material in a P-type gate limits P-type dopant out diffusion and, thereby ensures that the P-type gate-to-N-type channel region junction is more clearly defined (i.e., abrupt as opposed to graded). By clearly defining this junction, the depletion layer in the N-type channel region is extended. Extending the depletion layer in turn allows for a faster pinch off (i.e., requires lower Voff). P-type SiGe or SiGeC gate(s) can be incorporated into conventional lateral JFET structures and/or vertical JFET structures. Also disclosed herein are embodiments of a method of forming such a JFET structure.

Abstract: A semiconductor device with minimized current flow differences and method of fabricating same are disclosed. The method includes forming a semiconductor stack including a plurality of layers that include a first layer having a first conductivity type and a second layer having a first conductivity type, in which the second layer is on top of the first layer, forming a plurality of mesas in the semiconductor layer stack, and forming a plurality of gates in the semiconductor layer stack having a second conductivity type and situated partially at a periphery of the mesas, in which the plurality of gates are formed to minimize current flow differences between a current flowing from the first layer to the plurality of mesas at a first applied gate bias and a current flowing from the first layer to the plurality of mesas at a second applied gate bias when voltage is applied to the semiconductor device.

Abstract: In accordance with an aspect of the invention, A Schottky junction field effect transistor (JFET) is created using cobalt silicide, or other Schottky material, to form the gate contact of the JFET. The structural concepts can also be applied to a standard JFET that uses N? type or P? type dopants to form the gate of the JFET. In addition, the structures allow for an improved JFET linkup with buried linkup contacts allowing improved noise and reliability performance for both conventional diffusion (N? and P? channel) JFET structures and for Schottky JFET structures. In accordance with another aspect of the invention, the gate poly, as found in a standard CMOS or BiCMOS process flow, is used to perform the linkup between the source and the junction gate and/or between the drain and the junction gate of a junction filed effect transistor (JFET).

Abstract: An integrated circuit (100) in which a voltage divider circuit is integrated comprises a first resistor (121), second resistor (122), control portion (130), switch (140), and switching portion (150). The first resistor (121) and second resistor (122) form a resistive voltage divider element for dividing a voltage obtained by rectifying an alternating-current voltage, or a direct-current voltage, supplied to a control portion (130). The switch (140) is provided in series with the resistive voltage divider element, and passes or cuts off current passing through the resistive voltage divider element. The switching portion (150) switches the switch (140) so as to pass current during driving of the control portion (130), and cut off current during standby of the control portion (130).

Abstract: Disclosed is an HJFET 110 which comprises: a channel layer 12 composed of InyGa1-yN (0?y?1); a carrier supply layer 13 composed of AlxGa1-xN (0?x?1), the carrier supply layer 13 being provided over the channel layer 12 and including at least one p-type layer; and a source electrode 15S, a drain electrode 15D and a gate electrode 17 which are disposed facing the channel layer 12 through the p-type layer, and provided over the carrier supply layer 13. The following relational expression is satisfied: 5.6×1011x<NA×?×t [cm?2]<5.6×1013x, where x denotes an Al compositional ratio of the carrier supply layer, t denotes a thickness of the p-type layer, NA denotes an impurity concentration, and ? denotes an activation ratio.

Abstract: Fabricating high voltage transistors includes forming a buried p-type implant on a p-substrate for each transistor, the transistor having a source side and a drain side, wherein the p-type implant is positioned adjacent the source and is configured to extend under a gate region; depositing a low doping epitaxial layer on the p-substrate and the p-type implant for each high voltage transistor, the low doping epitaxial layer extending from the source to the drain; forming an N-Well in the low doping epitaxial layer for each transistor, wherein the N-Well corresponds to a low voltage transistor N-Well fabricated using a low voltage transistor fabrication process; and forming a p-top diffusion region in or on the N-Well for each transistor, wherein the p-top diffusion region is configured to compensate for a dopant concentration of the N-Well at or near a surface of the N-Well opposing the substrate.

Abstract: According to one embodiment, a self-aligned trench structure junction gate field-effect transistor (JFET) includes a silicon substrate, two or more trenches having a P-type polysilicon gate region near a bottom portion of the trench and an interlayer dielectric layer (ILDL) above the P-type polysilicon gate region, a channel region separating each trench including epitaxial silicon, an N+ source region above the channel region extending between a top of each trench, and a source metal above the N+ source region. In another embodiment, a self-aligned trench structure JFET includes a silicon substrate, two or more trenches having an N-type polysilicon gate region near a bottom portion of the trench and an ILDL above the N-type polysilicon gate region, a channel region separating each trench including epitaxial silicon, a P+ source region above the channel region extending between a top of each trench, and a source metal above the P+ source region.

Abstract: An improved structure of heterojunction field effect transistor (HFET) and a fabrication method thereof are disclosed. The improved HFET structure comprises sequentially a substrate, a channel layer, a spacing layer, a carrier supply layer, a Schottky layer, a Schottky capping layer formed by a higher energy gap material, a tunneling layer formed by a lower energy gap material, a first etching stop layer, and a first n type doped layer.

Abstract: A junction gate field-effect transistor (JFET) for an integrated circuit (IC) chip is provided comprising a source region, a drain region, a lower gate, and a channel, with an insulating shallow trench isolation (STI) region extending from an inner edge of an upper surface of the source region to an inner edge of an upper surface of the drain region, without an intentionally doped region, e.g., an upper gate, coplanar with an upper surface of the IC chip between the source/drain regions. In addition, an asymmetrical quasi-buried upper gate can be included, disposed under a portion of the STI region, but not extending under a portion of the STI region proximate to the drain region. Embodiments of this invention also include providing an implantation layer, under the source region, to reduce Ron. A related method and design structure are also disclosed.

Abstract: A junction field-effect transistor (20) comprises an n-type semiconductor layer (1) having a channel region, a buffer layer (3) formed on the channel region and a p+ region (4a, 4b) formed on the buffer layer (3). The concentration of electrons in the buffer layer (3) is lower than the concentration of electrons in the semiconductor layer (1). The concentration of electrons in the buffer layer (3) is preferably not more than one tenth of the concentration of electrons in the semiconductor layer (1). Thus, the threshold voltage can be easily controlled, and saturation current density of a channel can be easily controlled.

Abstract: There is provided a technique for reducing the occurrence of higher harmonics which occur from a field effect transistor, particularly a field effect transistor configuring a switching element of an antenna switch. In a transistor having a meander structure, the gate width of a partial transistor closest to a gate input side is increased. More specifically, a comb-like electrode is made longer than the other comb-like electrodes. In other words, a finger length is made greater than any other finger length. In particular, the comb-like electrode has the greatest length in all the comb-like electrodes.

Abstract: A low noise (1/f) junction field effect transistor (JFET) is disclosed, wherein multiple implants push a conduction path of the transistor away from the surface of a layer upon which the transistor is formed. In this manner, current flow in the conduction path is less likely to be disturbed by defects that may exist at the surface of the layer, thereby mitigating (1/f) noise.

Abstract: A semiconductor device as described herein includes a body region of a first conductivity type adjoining a channel region of a second conductivity at a first side of the channel region. A gate control region of the first conductivity type adjoins the channel region at a second side of the channel region opposed to the first side, the channel region being configured to be controlled in its conductivity by voltage application between the gate control region and the body region. A source zone of the second conductivity type is arranged within the body region and a channel stop zone of the second conductivity type is arranged at the first side, the channel stop zone being arranged at least partly within at least one of the body region and the channel region. The channel stop zone includes a maximum concentration of dopants lower than a maximum concentration of dopants of the source zone.

Abstract: A support substrate comprises first and second counter-electrodes arranged in the same plane at the level of a surface of the support substrate. An electrically insulating area separates the first and second counter-electrodes. A semi-conducting area with first and second portions is separated from the support substrate by an electrically insulating material. The electrically insulating material is different from the material forming the support substrate. The first portion of the semi-conducting area is facing the first counter-electrode. The second portion of the semi-conducting area is facing the second counter-electrode.

Abstract: Schottky barrier semiconductor devices are provided including a wide bandgap semiconductor layer and a gate on the wide bandgap semiconductor layer. The gate includes a metal layer on the wide bandgap semiconductor layer including a nickel oxide (NiO) layer. Related methods of fabricating devices are also provided herein.

Abstract: A nitride semiconductor device includes a first nitride semiconductor layer formed on a substrate, a defect induced layer formed on the first nitride semiconductor layer, and a second nitride semiconductor layer formed on the defect induced layer, contacting the defect induced layer, and having an opening through which the defect induced layer is exposed. The defect induced layer has a higher crystal defect density than those of the first and second nitride semiconductor layers.

Abstract: Methods, devices, and systems integrating Fin-JFETs and Fin-MOSFETs are provided. One method embodiment includes forming at least on Fin-MOSFET on a substrate and forming at least on Fin-JFET on the substrate.

Abstract: A semiconductor device includes a substrate, a compound semiconductor layer formed over the substrate, and a protective insulating film composed of silicon nitride, which is formed over a surface of the compound semiconductor layer and whose film density in an intermediate portion is lower than that in a lower portion.

Abstract: A nitride semiconductor device includes a first nitride semiconductor layer; a second nitride semiconductor layer formed on the first nitride semiconductor layer, and having a wider bad gap than the first nitride semiconductor layer; a source electrode, a drain electrode, and a gate electrode, which are formed on the second nitride semiconductor layer; a high resistive layer formed lower than the first nitride semiconductor layer; a conductive layer formed under and in contact with the high resistive layer; a lower insulating layer formed under the conductive layer; and a bias terminal electrically connected to the conductive layer.

Abstract: A non-volatile field-effect device. The non-volatile field-effect device includes a source, a drain, a channel-formation portion and a memristive gate. The channel-formation portion is disposed between and coupled with the source and the drain. The memristive gate is disposed over the channel-formation portion and coupled with the channel-formation portion. The memristive gate includes a plurality of mobile ions and a confinement structure for the plurality of mobile ions. Moreover, the memristive gate is configured to switch the channel-formation portion from a first conductivity state to a second conductivity state in response to migration of the plurality of mobile ions within the confinement structure.

Abstract: A semiconductor device having a JFET includes: a substrate made of semi-insulating semiconductor material; a gate region in a surface portion of the substrate; a channel region disposed on and contacting the gate region; a source region and a drain region disposed on both sides of the gate region so as to sandwich the channel region, respectively; a source electrode electrically coupled with the source region; a drain electrode electrically coupled with the drain region; and a gate electrode electrically coupled with the gate region. An impurity concentration of each of the source region and the drain region is higher than an impurity concentration of the channel region.

Abstract: A wide band gap semiconductor device having a JFET, a MESFET, or a MOSFET mainly includes a semiconductor substrate, a first conductivity type semiconductor layer, and a first conductivity type channel layer. The semiconductor layer is formed on a main surface of the substrate. A recess is formed in the semiconductor layer in such a manner that the semiconductor layer is divided into a source region and a drain region. The recess has a bottom defined by the main surface of the substrate and a side wall defined by the semiconductor layer. The channel layer has an impurity concentration lower than an impurity concentration of the semiconductor layer. The channel layer is formed on the bottom and the side wall of the recess by epitaxial growth.

Abstract: A lateral junction field-effect transistor capable of preventing the occurrence of leakage current and realizing a sufficient withstand voltage can be provided. In a lateral JFET according to the present invention, a buffer layer is located on a main surface of a SiC substrate and includes a p-type impurity. A channel layer is located on the buffer layer and includes an n-type impurity having a higher concentration than the concentration of the p-type impurity in the buffer layer. A source region and a drain region are of n-type and formed to be spaced from each other in a surface layer of the channel layer, and a p-type gate region is located in the surface layer of the channel layer and between the source region and the drain region. A barrier region is located in an interface region between the channel layer and the buffer layer and in a region located under the gate region and includes a p-type impurity having a higher concentration than the concentration of the p-type impurity in the buffer layer.

Abstract: A field effect transistor having a drain, a gate and a source, where the drain and source are formed by semiconductor regions of a first type, and in which a further doped region is provided intermediate the gate and the drain. Field gradients around the drain are thereby reduced.

Abstract: A single chip wireless sensor comprises a microcontroller connected by a transmit/receive interface to a wireless antenna. The microcontroller is also connected to an 8 kB RAM, a USB interface, an RS232 interface, 64 kB flash memory, and a 32 kHz crystal. The device senses humidity and temperature, and a humidity sensor is connected by an 18 bit ?? A-to-D converter to the microcontroller and a temperature sensor is connected by a 12 bit SAR A-to-D converter to the microcontroller. The device is an integrated chip manufactured in a single process in which both the electronics and sensor components are manufactured using standard CMOS processing techniques, applied to achieve both electronic and sensing components in an integrated process.

Abstract: A junction field effect transistor semiconductor device and method can include a top gate interposed between a source region and a drain region, and which can extend across an entire surface of the channel region from the source region to the drain region. Top gate doping can be configured such that the top gate can remain depleted throughout operation of the device. An embodiment of a device so configured can be used in precision, high-voltage applications.

Abstract: A 4-Terminal JFET includes a substrate having a first conduction type and an upper layer having a second, opposite, conduction type over the substrate. A gate and a source are embedded in the upper layer. A gate pad is electrically connected to the gate. A region, which has a first conduction type, is formed in the upper layer and separates the upper layer into two sections. This region reduces the overall capacitance between the gate pad and the source. Reduced overall gate to source capacitance can result in reduced noise amplification in the JFET.

Abstract: A semiconductor device and a fabrication method thereof are provided. The semiconductor device includes a semiconductor substrate which comprise a first type well and a second type well, and a plurality of junction regions therebetween, wherein each of the junction regions adjoins the first and the second type wells. A gate electrode disposed on the semiconductor substrate and overlies at least two of the junction regions. A source and a drain are in the semiconductor substrate oppositely adjacent to the gate electrode.