Abstract: The present invention discloses an enhanced mode high electron mobility transistor (HEMT) which includes: a P-type gallium nitride (GaN) layer; a barrier layer, which is formed on and connected to the GaN layer; a dielectric layer, which is formed on and connected to the GaN layer, wherein the barrier layer does not overlap at least part of the dielectric layer; a gate, which is formed on the dielectric layer for receiving a gate voltage; and a source and a drain, which are formed at two sides of the gate on the GaN layer respectively; wherein a two dimensional electron gas (2DEG) is formed at a junction of the GaN layer and the barrier layer which does not include a portion of the junction below the gate, and the 2DEG does not electrically connect the source to the drain when there is no voltage applied to the gate.

Abstract: The present invention discloses a high electron mobility transistor (HEMT) and a manufacturing method thereof. The HEMT includes a semiconductor layer, a barrier layer on the semiconductor layer, a piezoelectric layer on the barrier layer, a gate on the piezoelectric layer, and a source and a drain at two sides of the gate respectively, wherein each bandgap of the semiconductor layer, the barrier layer, and the piezoelectric layer partially but not entirely overlaps the other two bandgaps. The gate is formed for receiving a gate voltage. A two dimensional electron gas (2DEG) is formed in a portion of a junction between the semiconductor layer and the barrier layer but not below at least a portion of the piezoelectric layer, wherein the 2DEG is electrically connected to the source and the drain.

Abstract: A low leakage current transistor (2) is provided which includes a GaN-containing substrate (11-14) covered by a passivation surface layer (17) in which a T-gate electrode with sidewall extensions (20) is formed and coated with a multi-level passivation layer (30-32) which includes an intermediate etch stop layer (31) which is used to define a continuous multi-region field plate (33) having multiple distances between the bottom surface of the field plate 33 and the semiconductor substrate in the gate-drain region of the transistor.

Abstract: According to one embodiment, a nitride semiconductor device includes a first, a second and a third semiconductor layer, a first and a second main electrode and a control electrode. The first layer made of a nitride semiconductor of a first conductivity type is provided on a substrate. The second layer made of a nitride semiconductor of a second conductivity type is provided on the first layer. The third layer made of a nitride semiconductor is provided on the second layer. The first electrode is electrically connected with the second layer. The second electrode is provided at a distance from the first electrode and electrically connected with the second layer. The control electrode is provided within a first trench via an insulating film. The first trench is disposed between the first and the second main electrodes, penetrates the third and the second layers, and reaches the first layer.

Abstract: Semiconductor devices and methods of forming semiconductor devices are provided herein. In an embodiment, a semiconductor device includes a semiconductor substrate. A source region and a drain region are disposed in the semiconductor substrate. A channel region is defined in the semiconductor substrate between the source region and the drain region. A gate dielectric layer overlies the channel region of the semiconductor substrate, and a gate electrode overlies the gate dielectric layer. The channel region includes a first carbon-containing layer, a doped layer overlying the first carbon-containing layer, a second carbon-containing layer overlying the doped layer, and an intrinsic semiconductor layer overlying the second carbon-containing layer. The doped layer includes a dopant that is different than carbon.

Abstract: The compound semiconductor device comprises an i-GaN buffer layer 12 formed on an SiC substrate 10; an n-AlGaN electron supplying layer 16 formed on the i-GaN buffer layer 12; an n-GaN cap layer 18 formed on the n-AlGaN electron supplying layer 16; a source electrode 20 and a drain electrode 22 formed on the n-GaN cap layer 18; a gate electrode 26 formed on the n-GaN cap layer 18 between the source electrode 20 and the drain electrode 22; a first protection layer 24 formed on the n-GaN cap layer 18 between the source electrode 20 and the drain electrode 22; and a second protection layer 30 buried in an opening 28 formed in the first protection layer 24 between the gate electrode 26 and the drain electrode 22 down to the n-GaN cap layer 18 and formed of an insulation film different from the first protection layer.

Abstract: In some embodiments, a metal insulator semiconductor heterostructure field effect transistor (MISHFET) is disclosed that has a source, a drain, an insulation layer, a gate dielectric, and a gate. The source and drain are on opposing sides of a channel region of a channel layer. The channel region is an upper portion of the channel layer. The channel layer comprises gallium nitride. The insulation layer is over the channel layer and has a first portion and a second portion. The first portion is nearer the drain than the source and has a first thickness. The second portion is nearer the source than drain and has the first thickness. The insulation layer has an opening through the insulation layer. The opening is between the first portion and the second portion.

Abstract: A high electron mobility transistor (HEMT) includes a first III-V compound layer. A second III-V compound layer is disposed on the first III-V compound layer and is different from the first III-V compound layer in composition. A source feature and a drain feature are in contact with the second III-V compound layer. A n-type doped region underlies each source feature and drain feature in the second III-V compound layer. A p-type doped region underlies each n-type doped region in the first III-V compound layer. A gate electrode is disposed over a portion of the second III-V compound layer between the source feature and the drain feature.

Abstract: High electron mobility transistors and fabrication processes are presented in which a barrier material layer of uniform thickness is provided for threshold voltage control under an enhanced channel charge inducing material layer (ECCIML) in source and drain regions with the ECCIML layer removed in the gate region.

Abstract: The invention relates to a semiconductor device and a fabrication method thereof. A semiconductor device according to an aspect of the invention comprising: a semiconductor layer on a substrate; an isolation layer on the semiconductor layer; a source and a drain which are in contact with the semiconductor layer, each of the source and the drain comprises multiple fingers, and the multiple fingers of the source intersect the multiple fingers of the drain; and a gate on the isolation layer, the gate is located between the source and the drain and comprises a closed ring structure which encircles the multiple fingers of the source and the drain.

Abstract: There is provided a semiconductor device having a High Electron Mobility Transistor (HEMT) structure allowing for enhanced performance and a method of manufacturing the same. The semiconductor device includes a base substrate; a semiconductor layer provided on the base substrate; a source electrode, a gate electrode and a drain electrode provided on the semiconductor layer to be spaced apart from one another; and an ohmic-contact layer partially provided at an interface between the drain electrode and the semiconductor layer.

Abstract: Embodiments of the present disclosure describe techniques and configurations to impart strain to integrated circuit devices such as horizontal field effect transistors. An integrated circuit device includes a semiconductor substrate, a first barrier layer coupled with the semiconductor substrate, a quantum well channel coupled to the first barrier layer, the quantum well channel comprising a first material having a first lattice constant, and a source structure coupled to the quantum well channel, the source structure comprising a second material having a second lattice constant, wherein the second lattice constant is different than the first lattice constant to impart a strain on the quantum well channel. Other embodiments may be described and/or claimed.

Abstract: Provided is a method of fabricating a semiconductor device. The method includes forming a first III-V family layer over a substrate. The first III-V family layer includes a surface having a first surface morphology. The method includes performing an ion implantation process to the first III-V family layer through the surface. The ion implantation process changes the first surface morphology into a second surface morphology. After the ion implantation process is performed, the method includes forming a second III-V family layer over the first III-V family layer. The second III-V family layer has a material composition different from that of the first III-V family layer.

Abstract: An integrated circuit structure includes a substrate and a first and a second plurality of III-V semiconductor layers. The first plurality of III-V semiconductor layers includes a first bottom barrier over the substrate; a first channel layer over the first bottom barrier; and a first top barrier over the first channel layer. A first field-effect transistor (FET) includes a first channel region, which includes a portion of the first channel layer. The second plurality of III-V semiconductor layers is over the first plurality of III-V semiconductor layers and includes a second bottom barrier; a second channel layer over the second bottom barrier; and a second top barrier over the second channel layer. A second FET includes a second channel region, which includes a portion of the second channel layer.

Abstract: A semiconductor structure includes a first III-V compound layer. A second III-V compound layer is disposed on the first III-V compound layer and is different from the first III-V compound layer in composition. A source feature and a drain feature are disposed on the second III-V compound layer. A gate electrode is disposed over the second III-V compound layer between the source feature and the drain feature. A fluorine region is embedded in the second III-V compound layer under the gate electrode. A gate dielectric layer is disposed over the second III-V compound layer. The gate dielectric layer has a fluorine segment on the fluorine region and under at least a portion of the gate electrode.

Abstract: A semiconductor structure includes a first III-V compound layer. A second III-V compound layer is disposed on the first III-V compound layer and is different from the first III-V compound layer in composition. The second III-V compound layer has a top surface. A source feature and a drain feature are disposed on the second III-V compound layer. A gate electrode is disposed over the second III-V compound layer between the source feature and the drain feature. A fluorine region is embedded in the second III-V compound layer under the gate electrode. The fluorine region has a top surface lower than the top surface of the second III-V compound layer. A gate dielectric layer is disposed under at least a portion of the gate electrode and over the fluorine region.

Abstract: An enhancement-mode GaN MOSFET with a low leakage current and an improved reliability is formed by utilizing a SiO2/Si3N4 gate insulation layer on an AlGaN (or InAlGaN) barrier layer. The Si3N4 portion of the SiO2/Si3N4 gate insulation layer significantly reduces the formation of interface states at the junction between the gate insulation layer and the barrier layer, while the SiO2 portion of the SiO2/Si3N4 gate insulation layer significantly reduces the leakage current.

Abstract: Embodiments of the present disclosure describe apparatuses, methods, and systems of an integrated circuit (IC) device. The IC device may include a buffer layer disposed on a substrate, the buffer layer including gallium (Ga) and nitrogen (N), a barrier layer disposed on the buffer layer, the barrier layer including aluminum (Al) and nitrogen (N), a regrown structure disposed in and epitaxially coupled with the barrier layer, the regrown structure including nitrogen (N) and at least one of aluminum (Al) or gallium (Ga) and being epitaxially deposited at a temperature less than or equal to 600° C., and a gate terminal disposed in the barrier layer, wherein the regrown structure is disposed between the gate terminal and the buffer layer. Other embodiments may be described and/or claimed.

Abstract: A semiconductor structure includes a high mobility semiconductor, an interfacial oxide layer, a high dielectric constant (high-k) layer, a stack, a gate electrode, and a gate dielectric. The stack comprises a lower metal layer, a scavenging metal layer comprising a scavenging metal, and an upper metal layer formed on the scavenging metal layer. A Gibbs free energy change of a chemical reaction, in which an atom constituting the high mobility semiconductor layer that directly contacts the interfacial oxide layer combines with a metal oxide material comprising the scavenging metal and oxygen to form the scavenging metal in elemental form and oxide of the atom constituting the high mobility semiconductor layer that directly contacts the interfacial oxide layer, is positive.

Abstract: A diode and a method of making same has a cathode an anode and one or more semiconductor layers disposed between the cathode and the anode. A dielectric layer is disposed between at least one of the one or more semiconductor layers and at least one of the cathode or anode, the dielectric layer having one or more openings or trenches formed therein through which the at least one of said cathode or anode projects into the at least one of the one or more semiconductor layers, wherein a ratio of a total surface area of the one or more openings or trenches formed in the dielectric layer at the at least one of the one or more semiconductor layers to a total surface area of the dielectric layer at the at least one of the one or more semiconductor layers is no greater than 0.25.

Abstract: A semiconductor device and a fabrication method of the semiconductor device, the semiconductor device including: a substrate; a nitride based compound semiconductor layer placed on the substrate and doped with a first transition metal atom; an aluminum gallium nitride layer (AlxGa1-xN) (where 0.1<=x<=1) placed on the nitride based compound semiconductor layer; a nitride based compound semiconductor layer placed on the aluminum gallium nitride layer (AlxGa1-xN) (where 0.1<=x<=1) and doped with a second transition metal atom; an aluminum gallium nitride layer (AlyGa1-yN) (where 0.1<=y<=1) placed on the nitride based compound semiconductor layer doped with the second transition metal atom; and a gate electrode, a source electrode, and a drain electrode which are placed on the aluminum gallium nitride layer (AlyGa1-yN) (where 0.1<=y<=1).

Abstract: A transistor device includes a semiconductor heterostructure including a plurality of alternating two-dimensional electron gasses (2DEGs) and two-dimensional hole gasses (2DHGs) extending in parallel at different depths in the semiconductor heterostructure. The 2DEGs form current channels of the transistor device. The transistor device further includes a source extending into the semiconductor heterostructure in contact with the 2DEGs at a first end of the current channels, and a drain extending into the semiconductor heterostructure in contact with the 2DEGs at an opposing second end of the current channels. The transistor device also includes a plurality of spaced apart gate structures extending into the semiconductor heterostructure and including an electrically conductive material separated from the surrounding semiconductor heterostructure by an insulating material.

Abstract: An embodiment of the present invention concerns a layered epitaxial structure for enhancement/depletion PHEMT devices, an enhancement/depletion PHEMT device and a method for manufacturing an enhancement/depletion PHEMT device that finds advantageous, but not exclusive, application in the manufacturing of integrated circuits operating at millimeter-wave and microwave frequencies.

Abstract: Techniques for employing different channel materials within the same CMOS circuit are provided. In one aspect, a method of fabricating a CMOS circuit includes the following steps. A wafer is provided having a first semiconductor layer on an insulator. STI is used to divide the first semiconductor layer into a first active region and a second active region. The first semiconductor layer is recessed in the first active region. A second semiconductor layer is epitaxially grown on the first semiconductor layer, wherein the second semiconductor layer comprises a material having at least one group III element and at least one group V element. An n-FET is formed in the first active region using the second semiconductor layer as a channel material for the n-FET. A p-FET is formed in the second active region using the first semiconductor layer as a channel material for the p-FET.

Abstract: A normally-off transistor includes a channel layer, an electron supply layer overlaying the channel layer, a source electrode and a drain electrode on the electron supply layer, an area in the electrode supply layer between the source electrode and the drain electrode treated with a fluoride based plasma followed by a chlorine based plasma treatment, a gate insulator overlaying the area, and a gate electrode overlaying the gate insulator.

Abstract: A vertical type GaN series field effect transistor having excellent pinch-off characteristics is provided. A compound semiconductor device includes a conductive semiconductor substrate, a drain electrode formed on a bottom surface of the conductive semiconductor substrate, a current blocking layer formed on a top surface of the conductive semiconductor substrate, made of high resistance compound semiconductor or insulator, and having openings, an active layer of compound semiconductor burying the openings and extending on an upper surface of the current blocking layer, a gate electrode formed above the openings and above the active layer, and a source electrode formed laterally spaced from the gate electrode and formed above the active layer.

Abstract: A transistor device includes a compound semiconductor body having a first surface and a two-dimensional charge carrier gas disposed below the first surface in the compound semiconductor body. The transistor device further includes a source in contact with the two-dimensional charge carrier gas and a drain spaced apart from the source and in contact with the two-dimensional charge carrier gas. A first passivation layer is in contact with the first surface of the compound semiconductor body, and a second passivation layer is disposed on the first passivation layer. The second passivation layer has a different etch rate selectivity than the first passivation layer. A gate extends through the second passivation layer into the first passivation layer.

Abstract: Embodiments of the present disclosure describe apparatuses, methods, and systems of an integrated circuit (IC) device. The IC device may include a buffer layer disposed on a substrate, the buffer layer including gallium (Ga) and nitrogen (N), a barrier layer disposed on the buffer layer, the barrier layer including aluminum (Al) and nitrogen (N), wherein the barrier layer includes an oxidized portion of the barrier layer, a gate dielectric disposed on the oxidized portion of the barrier layer, and a gate electrode disposed on the gate dielectric, wherein the oxidized portion of the barrier layer is disposed in a gate region between the gate electrode and the buffer layer.

Abstract: An improved pseudomorphic high electron mobility transistor (pHEMT) and heterojunction bipolar transistor (HBT) integrated epitaxial structure and the fabrication method thereof, in which the structure comprises a substrate, a pHEMT structure, an etching-stop spacer layer, and an HBT structure. The pHEMT's structure comprises a buffer layer, a barrier layer, a first channel spacer layer, a channel layer, a second channel spacer layer, a Schottky barrier layer, an etching-stop layer, and at least one cap layer. The fabrication method of an HBT and a pHEMT are also included.

Abstract: An n-layer is arranged above a substrate, which can be GaAs, and a p-layer (4) is arranged on the n-layer. The p-layer is separated by a gate electrode into two separate portions forming source and drain. The gate electrode is insulated from the semiconductor material by a gate dielectric. Source/drain contacts are electrically conductively connected with the portions of the p-layer.

Abstract: A high electron mobility field effect transistor (HEMT) having a substrate, a channel layer on the substrate and a barrier layer on the channel layer includes a stress inducing layer on the barrier layer, the stress inducing layer varying the piezo-electric effect in the barrier layer in a drift region between a gate and a drain. A two dimensional electron gas (2DEG) has a non-uniform lateral distribution in the drift region between the gate and the drain.

Abstract: A HEMT device has a substrate; a buffer layer disposed above the substrate; a carrier supplying layer disposed above the buffer layer; a gate element penetrating the carrier supplying layer; and a drain element disposed on the carrier supplying layer. The carrier supplying layer has a non-uniform thickness between the gate element and the drain element, the carrier supplying layer having a relatively greater thickness adjacent the drain element and a relatively thinner thickness adjacent the gate element. A non-uniform two-dimensional electron gas conduction channel is formed in the carrier supplying layer, the two-dimensional electron gas conduction channel having a non-uniform profile between the gate and drain elements.

Abstract: A high electron mobility field effect transistor (HEMT) includes a two dimensional electron gas (2DEG) in the drift region between the gate and the drain that has a non-uniform lateral 2DEG distribution that increases in a direction in the drift region from the gate to the drain.

Abstract: Embodiments of the present disclosure describe apparatuses, methods, and systems of a device such as a transistor. The device includes a buffer layer disposed on a substrate, the buffer layer being configured to serve as a channel of a transistor and including gallium (Ga) and nitrogen (N), a barrier layer disposed on the buffer layer, the barrier layer being configured to supply mobile charge carriers to the channel and including aluminum (Al), gallium (Ga), and nitrogen (N), a charge-inducing layer disposed on the barrier layer, the charge-inducing layer being configured to induce charge in the channel and including aluminum (Al) and nitrogen (N), and a gate terminal disposed in the charge-inducing layer and coupled with the barrier layer to control the channel. Other embodiments may also be described and/or claimed.

Abstract: A transistor includes a first semiconductor layer formed on a substrate, a second semiconductor layer formed on the first semiconductor layer and has a band gap larger than that of the first semiconductor layer, a control layer formed on the second semiconductor layer and contains p-type impurities, a gate electrode formed in contact with at least part of the control layer and a source electrode and a drain electrode formed on both sides of the control layer, respectively. A third semiconductor layer made of material having a lower etch rate than that of the control layer is formed between the control layer and the second semiconductor layer.

Abstract: Disclosed is a semiconductor device. More specifically, disclosed are a nitride-based heterojunction semiconductor device and a method for producing the same. The nitride-based heterojunction semiconductor device includes a nitride semiconductor buffer layer, a barrier layer disposed on the buffer layer, a cap layer discontinuously disposed on the barrier layer, a source electrode and a drain electrode that contact at least one of the barrier layer and the cap layer, and a gate electrode that Schottky-contacts at least one of the barrier layer and the cap layer and is disposed between the source electrode and the drain electrode.

Abstract: A method for fabricating edge termination structures in gallium nitride (GaN) materials includes providing a n-type GaN substrate having a first surface and a second surface, forming an n-type GaN epitaxial layer coupled to the first surface of the n-type GaN substrate, and forming a growth mask coupled to the n-type GaN epitaxial layer. The method further includes patterning the growth mask to expose at least a portion of the n-type GaN epitaxial layer, and forming at least one p-type GaN epitaxial structure coupled to the at least a portion of the n-type GaN epitaxial layer. The at least one p-type GaN epitaxial structure comprises at least one portion of an edge termination structure. The method additionally includes forming a first metal structure electrically coupled to the second surface of the n-type GaN substrate.

Abstract: A HEMT comprising a plurality of active semiconductor layers formed on a substrate. Source electrode, drain electrode, and gate are formed in electrical contact with the plurality of active layers. A spacer layer is formed on at least a portion of a surface of said plurality of active layers and covering the gate. A field plate is formed on the spacer layer and electrically connected to the source electrode, wherein the field plate reduces the peak operating electric field in the HEMT.

Abstract: A semiconductor device including a low conducting field-controlling element is provided. The device can include a semiconductor including an active region, and a set of contacts to the active region. The field-controlling element can be coupled to one or more of the contacts in the set of contacts. The field-controlling element can be formed of a low conducting layer having a sheet resistance between approximately 103 Ohms per square and approximately 107 Ohms per square. During direct current and/or low frequency operation, the field-controlling element can behave similar to a metal electrode. However, during high frequency operation, the field-controlling element can behave similar to an insulator.

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: An embodiment of a compound semiconductor device includes: a substrate; an electron channel layer and an electron supply layer formed over the substrate; a gate electrode, a source electrode and a drain electrode formed on or above the electron supply layer; and a p-type semiconductor layer formed between the electron supply layer and the gate electrode. The p-type semiconductor layer contains, as a p-type impurity, an element same as that being contained in at least either of the electron channel layer and the electron supply layer.

Abstract: Two layers of protection films are formed such that a sheet resistance at a portion directly below the protection film is higher than that at a portion directly below the protection film. The protection films are formed, for example, of SiN film, as insulating films. The protection film is formed to be higher, for instance, in hydrogen concentration than the protection film so that the protection film is higher in refractive index the protection film. The protection film is formed to cover a gate electrode and extend to the vicinity of the gate electrode on an electron supplying layer. The protection film is formed on the entire surface to cover the protection film. According to this configuration, the gate leakage is significantly reduced by a relatively simple configuration to realize a highly-reliable compound semiconductor device achieving high voltage operation, high withstand voltage, and high output.

Abstract: An Enhancement-mode (E-mode) high electron mobility transistor (HEMT) includes a channel layer with a 2-Dimensional Electron Gas (2DEG), a barrier layer inducing the 2DEG in the channel layer, source and drain electrodes on the barrier layer, a depletion layer on the barrier layer between the source and drain electrodes, and a gate electrode on the depletion layer. The barrier layer is recessed below the gate electrode and the depletion layer covers a surface of the recess and extends onto the barrier layer around the recess.

Abstract: The present invention provides a transistor and a method for forming the same. The method includes: providing a semiconductor substrate having a semiconductor layer formed thereon, the semiconductor layer and the semiconductor substrate having different crystal orientations; forming a dummy gate structure on the semiconductor layer; forming a source region and a drain region in the semiconductor substrate and the semiconductor layer and at opposite sides of the dummy gate structure; forming an interlayer dielectric layer on the semiconductor layer, which is substantially flush with the dummy gate structure; removing the dummy gate structure and the semiconductor layer beneath the dummy gate structure, forming an opening in the interlayer dielectric layer and the semiconductor layer, the semiconductor substrate being exposed at a bottom of the opening; forming a metal gate structure in the opening. Saturation current of the transistor is raised, and performance of a semiconductor device is promoted.

Abstract: A field-effect transistor includes a first semiconductor layer formed on a substrate, and a second semiconductor layer. The first semiconductor layer has a containing region provided as an isolation region which contains non-conductive impurities, and a non-containing region which contains no non-conductive impurities. A first region is defined by a vicinity of a portion of the interface between the containing region and the non-containing region, the portion of the interface being below a gate electrode, the vicinity including the portion of the interface and being included in the containing region. The second semiconductor layer includes a second region which is located directly above the first region. The concentration of the non-conductive impurities of the second region is lower than that of the first region.

Abstract: Systems, methods, and apparatus described herein are associated with devices including hybrid electrodes. A heterostructure semiconductor transistor can include a III-N-type semiconductor heterostructure including a barrier layer overlying an active layer and a hybrid electrode region including a hybrid drain electrode region. Further, a heterostructure semiconductor rectifier can include a III-N-type semiconductor heterostructure and a hybrid electrode region including a hybrid cathode electrode region. Furthermore, the hybrid electrode region of the transistor and rectifier can include permanently trapped charge located under a Schottky contact of the hybrid electrode region.

Abstract: A method for fabricating an electronic device, comprising wafer bonding a first semiconductor material to a III-nitride semiconductor, at a temperature below 550° C., to form a device quality heterojunction between the first semiconductor material and the III-nitride semiconductor, wherein the first semiconductor material is different from the III-nitride semiconductor and is selected for superior properties, or preferred integration or fabrication characteristics in the injector region as compared to the III-nitride semiconductor.

Abstract: A method for fabricating a gate structure for a field effect transistor having a buffer layer on a substrate, a channel layer and a barrier layer over the channel layer includes forming a gate including silicon, forming first sidewalls of a first material on either side and adjacent to the gate, selectively etching into the buffer layer to form a mesa for the field effect transistor, depositing a material layer over the mesa, planarizing the material layer over the mesa to form a planarized surface such that a top of the gate, tops of the first sidewalls, and a top of the material layer over the mesa are on the same planarized surface, depositing metal on the planzarized surface, annealing to form the gate into a metal silicided gate, and etching to remove excess non-silicided metal.

Abstract: The present invention relates to an enhancement normally off nitride semiconductor device and a method of manufacturing the same. The method includes the steps of: forming a buffer layer on a substrate; forming a first nitride semiconductor layer on the buffer layer; forming a second nitride semiconductor layer on the first nitride semiconductor layer; etching a gate region above the second nitride semiconductor layer up to a predetermined depth of the first nitride semiconductor layer; forming an insulating film on the etched region and the second nitride semiconductor layer; patterning a source/drain region, etching the insulating film in the source/drain region, and forming electrodes in the source/drain region; and forming a gate electrode on the insulating film in the gate region. In this manner, the present invention provides a method of easily implementing a normally off enhancement semiconductor device by originally blocking 2DEG which is generated under a gate region.

Abstract: A nitride semiconductor device includes: a main semiconductor region comprising a first nitride semiconductor layer having a first band gap, and a second nitride semiconductor layer having a second band gap larger than the first band gap, a heterojunction being formed between the first nitride semiconductor layer and a the second nitride semiconductor layer such that two-dimensional electron gas layer can be caused inside the first nitride semiconductor layer based on the heterojunction; a source electrode formed on the main semiconductor region; a drain electrode formed on the main semiconductor region and separated from the source electrode; a third nitride semiconductor layer formed on the first nitride semiconductor layer and between the source electrode and the drain electrode; and a gate electrode formed on the third nitride semiconductor layer. The third nitride semiconductor layer has a third band gap smaller than the first band gap.