Abstract: A HEMT comprising a channel layer of a first III-Nitride semiconductor material, grown on a N-polar surface of a back barrier layer of a second III-Nitride semiconductor material; the second III-Nitride semiconductor material having a larger band gap than the first III-Nitride semiconductor material, such that a positively charged polarization interface and two-dimensional electron gas is obtained in the channel layer; a passivation, capping layer, of said first III-Nitride semiconductor material, formed on top of and in contact with a first portion of a N-polar surface of said channel layer; a gate trench traversing the passivation, capping layer, and ending at said N-polar surface of said channel layer; and a gate conductor filling said gate trench.

Abstract: The transistor 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 carrier channel is located between the first III-V compound layer and the second III-V compound layer. A source feature and a drain feature are disposed on the second III-V compound layer.

Abstract: A semiconductor structure includes a substrate, a stacked structure on the substrate, an insulating layer on the stacked structure, a passivation layer on the insulating layer, and a contact structure through the passivation layer and the insulating layer and directly contacting the stacked structure. The insulating layer has an extending portion protruding from a sidewall of the passivation layer and adjacent to a surface of the stacked structure directly contacting the contact structure.

Abstract: The present invention provides a method of forming an insulating structure of a high electron mobility transistor (HEMT), firstly, a gallium nitride layer is formed, next, an aluminum gallium nitride layer is formed on the gallium nitride layer, then, a first patterned photoresist layer is formed on the aluminum gallium nitride layer, and a groove is formed in the gallium nitride layer and the aluminum gallium nitride layer, next, an insulating layer is formed and filling up the groove. Afterwards, a second patterned photoresist layer is formed on the insulating layer, wherein the pattern of the first patterned photoresist layer is complementary to the pattern of the second patterned photoresist layer, and part of the insulating layer is removed, then, the second patterned photoresist layer is removed, and an etching step is performed on the remaining insulating layer to remove part of the insulating layer again.

Abstract: An embodiment of a semiconductor device includes a semiconductor substrate, a first dielectric layer, a first current-carrying electrode, and a second current-carrying electrode formed over the semiconductor substrate. A control electrode is formed over the semiconductor substrate and disposed between the first current-carrying electrode and the second current-carrying electrode. A conductive element formed over the first dielectric layer, adjacent the control electrode, and between the control electrode and the second current-carrying electrode, includes a first region formed a first distance from the upper surface of the semiconductor substrate and a second region formed a second distance from the upper surface of the semiconductor substrate. An insulating region is formed between the control electrode and the conductive element.

Abstract: A semiconductor device includes a substrate, a semiconductor channel layer, a semiconductor barrier layer, and a gate electrode. The semiconductor channel layer is disposed on the substrate, and the semiconductor barrier layer is disposed on the semiconductor channel layer, where the surface of the semiconductor barrier layer includes at least one recess. The gate electrode is disposed on the semiconductor barrier layer and includes a body portion and at least one vertical extension portion overlapping the recess.

Abstract: Disclosed are a transistor and a method for forming the transistor. The method includes concurrently forming gate and source/drain openings through an uppermost layer (i.e., a dielectric layer) in a stack of layers. The method can further include: depositing and patterning gate conductor material so that a first gate section is in the gate opening and a second gate section is above the gate opening and so that the source/drain openings are exposed; extending the depth of the source/drain openings; and depositing and patterning source/drain conductor material so that a first source/drain section is in each source/drain opening and a second source/drain section is above each source/drain opening. Alternatively, the method can include: forming a plug in the gate opening and sidewall spacers in the source/drain openings; extending the depth of source/drain openings; depositing and patterning the source/drain conductor material; and subsequently depositing and patterning the gate conductor material.

Abstract: The current disclosure describes a vertical tunnel FET device including a vertical P-I-N heterojunction structure of a P-doped nanowire gallium nitride source/drain, an intrinsic InN layer, and an N-doped nanowire gallium nitride source/drain. A high-K dielectric layer and a metal gate wrap around the intrinsic InN layer.

Abstract: According to one embodiment, a semiconductor device includes first, second, third nitride members, first, second, third electrodes, and a first insulating member. The first nitride member includes a first face along a first plane, a second face along the first plane, and a third face. The third face is connected with the first and second faces between the first and second faces. The third face crosses the first plane. The first face overlaps a part of the first nitride member. The second nitride member includes a first nitride region provided at the first face. The third nitride member includes a first nitride portion provided at the second face. The first electrode includes a first connecting portion. The second electrode includes a second connecting portion. The third electrode includes a first electrode portion. The first insulating member includes a first insulating region.

Abstract: A method of forming a semiconductor device includes forming a photoresist over a target layer, where the target layer includes a substrate. The photoresist is patterned to form a patterned photoresist. Scum remains between portions of the patterned photoresist. The substrate is tilted relative to a direction of propagation of an ion beam. An ion treatment is performed on the scum. A pattern of the patterned photoresist is transferred to the target layer.

Abstract: A method for fabricating a high electron mobility transistor (HEMT) includes the steps of first forming a buffer layer on a substrate, forming a barrier layer on the buffer layer, forming a p-type semiconductor layer on the barrier layer, forming a compressive stress layer adjacent to one side of the p-type semiconductor layer, and then forming a tensile stress layer adjacent to another side of the p-type semiconductor layer.

Abstract: A nitride semiconductor device includes: a substrate; a first nitride semiconductor layer; a second nitride semiconductor layer; a first opening penetrating through the second nitride semiconductor layer to the first nitride semiconductor layer; a second opening penetrating through the second nitride semiconductor layer to the first nitride semiconductor layer; an electron transport layer and an electron supply layer provided along an inner face of each of the first opening and the second opening and above the second nitride semiconductor layer; a gate electrode; an anode electrode; a third opening penetrating through the electron supply layer and the electron transport layer to the second nitride semiconductor layer; a source electrode in the third opening; a drain electrode; and a cathode electrode. The anode electrode and the source electrode are electrically connected, and the cathode electrode and the drain electrode are electrically connected.

Abstract: Apparatuses and methods for manufacturing semiconductor memory devices are described. An example method includes: forming a conductive layer and sputtering the conductive layer with gas. The conductive layer includes a first portion having a top surface having a first height; and a second portion having a top surface having a second height lower than the first height. Sputtering the conductive layer with gas may be performed to remove the first portion of the conductive layer and increase the second height of the second portion of the conductive layer concurrently.

Abstract: A high electron mobility transistor includes a substrate. A first III-V compound layer is disposed on the substrate. A second III-V compound layer is embedded within the first III-V compound layer. A P-type gallium nitride gate is embedded within the second III-V compound layer. A gate electrode is disposed on the second III-V compound layer and contacts the P-type gallium nitride gate. A source electrode is disposed at one side of the gate electrode. A drain electrode is disposed at another side of the gate electrode.

Abstract: A method including forming a III-V compound layer on a substrate and implanting a main dopant in the III-V compound layer to form source and drain regions. The method further includes implanting a group V species into the source and drain regions. A semiconductor device including a substrate and a III-V compound layer over the substrate. The semiconductor device further includes source and drain regions in the III-V layer, wherein the source and drain regions comprises a first dopants and a second dopant, and the second dopant comprises a group V material.

Abstract: Laterally-gated transistors and lateral Schottky diodes are disclosed. The FET includes a substrate, source and drain electrodes, channel, a gate electrode structure, and a dielectric layer. The gate electrode structure includes an electrode in contact with the channel and a lateral field plate adjacent to the electrode. The dielectric layer is disposed between the lateral field plate and the channel. The lateral field plate contacts the dielectric layer and to modulate an electric field proximal to the gate electrode proximal to the drain or source electrodes. Also disclosed is a gate electrode structure with lateral field plates symmetrically disposed relative to the gate electrode. Also disclosed in a substrate with dielectric structures buried in the substrate remote from the gate electrode structure. A lateral Schottky diode having an anode structure includes an anode (A), cathodes (C) and lateral field plates located between the anode and the cathodes.

Abstract: According to one embodiment, a semiconductor device includes first to third electrodes, first to third nitride regions, and first and second insulating films. The first nitride region includes Alx1Ga1?x1N, and includes first and second partial regions, a third partial region between the first and second partial regions, a fourth partial region between the first and third partial regions, and a fifth partial region between the third and second partial regions. The first nitride region includes first to fifth partial regions. The second nitride region includes Alx2Ga1?x2N, and sixth and seventh partial regions. At least a portion of the third electrode is between the sixth and seventh partial regions. The first insulating film includes silicon and oxygen and includes first and second insulating regions. The third nitride region includes Alx3Ga1?x3N, and first to seventh portions. The second insulating film includes silicon and oxygen and includes third to seventh insulating regions.

Abstract: A semiconductor structure is provided. The semiconductor structure includes a substrate, a channel layer, a barrier layer, a compound semiconductor layer, a gate electrode, and a stack of dielectric layers. The channel layer is disposed on the substrate. The barrier layer is disposed on the channel layer. The compound semiconductor layer is disposed on the barrier layer. The gate electrode is disposed on the compound semiconductor layer. The stack of dielectric layers is disposed on the gate electrode. The stack of dielectric layers includes layers having different etching rates.

Abstract: A method of manufacturing a vertical FET device includes providing a semiconductor substrate structure including a marker layer; forming a hardmask layer coupled to the semiconductor substrate structure, wherein the hardmask layer comprises a set of openings operable to expose an upper surface portion of the semiconductor substrate structure; etching the upper surface portion of the semiconductor substrate structure to form a plurality of fins; etching at least a portion of the marker layer; detecting the etching of the at least a portion of the marker layer; epitaxially growing a semiconductor layer in recess regions disposed between adjacent fins of the plurality of fins; forming a source metal layer on each of the plurality of fins; and forming a gate metal layer coupled to the semiconductor layer.

Abstract: A method of fabricating a HEMT includes the following steps. A substrate having a group III-V channel layer, a group III-V barrier layer, a group III-V gate layer, and a gate etch stop layer disposed thereon is provided. A passivation layer is formed to cover the group III-V barrier layer and the gate etch stop layer. A gate contact hole and at least one source/drain contact hole are formed in the passivation layer, where the gate contact hole exposes the gate etch stop layer, and the at least one source/drain contact hole exposes the group III-V channel layer. In addition, a conductive layer is conformally disposed on a top surface of the passivation layer and in the gate contact hole and the at least one source/drain contact hole.

Abstract: A sacrificial substrate wafer is provided. A low resistivity etch stop layer is formed on or in the top surface of the wafer. The etch stop layer may be a highly doped, p+ type epitaxially grown layer, or an implanted p+ type boron layer, or an epitaxially grown p+ type SiGe layer. Various epitaxial layers, such as an n? type drift layer, and doped regions are then formed over the etch stop layer to form a vertical power device. The starting wafer is then removed by a combination of mechanical grinding/polishing to leave a thinner layer of the starting wafer. A chemical or plasma etch is then used to remove the remainder of the starting wafer, using the etch stop layer to automatically stop the etching. A bottom metal electrode is then formed on the etch stop layer. The etch stop layer injects hole carriers into the drift layer.

Abstract: Semiconductor device structures and methods for manufacturing the same are provided. The semiconductor device structure includes a substrate, a first nitride semiconductor layer, a second nitride semiconductor layer, a barrier layer, a third nitride semiconductor layer and a gate structure. The first nitride semiconductor layer is disposed on the substrate. The second nitride semiconductor layer is disposed on the first nitride semiconductor layer and has a bandgap greater than that of the first nitride semiconductor layer. The barrier layer is disposed on the second nitride semiconductor layer and has a bandgap greater than that of the second nitride semiconductor layer. The third nitride semiconductor layer is doped with impurity and disposed on the barrier layer. The gate structure is disposed on the third nitride semiconductor layer.

Abstract: A multi-gate HEMT includes at least two gates, with at least one recessed the same depth or at a deeper depth in a barrier layer than at least one other gate. Recessing a gate decreases the thickness of the barrier layer beneath the gate, reducing a density of high mobility carriers in a two-dimensional electron gas layer (2DEG) conductive channel formed at the heterojunction of a barrier layer and a buffer layer below the recessed gate. The recessed gate can increase gate control of the 2DEG conductive channel. The multi-gate HEMT has at least one gate recessed the same depth or a deeper depth into the buffer layer than another gate, which forms at least two different turn-on voltages for different gates. This can achieve improvement of transconductance linearity and a positive shift of the threshold voltage.

Abstract: A method fabricating a GaN based sensor including: forming a gate dielectric layer over a GaN hetero-structure including a GaN layer formed over a substrate and a first barrier layer formed over the GaN layer; forming a first mask over the gate dielectric layer; etching the gate dielectric layer and the first barrier layer through the first mask, thereby forming source and drain contact openings; removing the first mask; forming a metal layer over the gate dielectric layer, wherein the metal layer extends into the source and drain contact openings; forming a second mask over the metal layer; etching the metal layer, the gate dielectric layer and the GaN heterostructure through the second mask, wherein a region of the GaN heterostructure is exposed; and thermally activating the metal layer in the source and drain contact openings. The gate dielectric may exhibit a sloped profile, and dielectric spacers may be formed.

Abstract: A process of preparing a wafer having a diameter of two inches or more, at least a surface of the wafer being formed from a group III nitride crystal, including preparing an alkaline or acidic etching liquid containing a peroxodisulfate ion as an oxidizing agent that accepts an electron, accommodating the wafer such that the surface of the wafer is immersed in the etching liquid such that the surface of the wafer is parallel with a surface of the etching liquid; and radiating light from the surface side of the etching liquid onto the surface of the wafer without agitating the etching liquid. First and second etching areas disposed at an interval from each other are defined on the surface of the wafer. In the process of radiating the light onto the surface of the wafer, the light is radiated perpendicularly onto surfaces of the first and second etching areas.

Abstract: A semiconductor device includes a substrate, a first GaN-based high-electron-mobility transistor (HEMT), a second GaN-based HEMT, a first interconnection, and a second interconnection is provided. The substrate has a plurality of first-type doped semiconductor regions and second-type doped semiconductor regions. The first GaN-based HEMT is disposed over the substrate to cover a first region on the first-type doped semiconductor regions and the second-type doped semiconductor regions in the substrate. The second GaN-based HEMT is disposed over the substrate to cover a second region. The first region is different from the second region. The first interconnection is disposed over and electrically connected to the substrate, forming a first interface. The second interconnection is disposed over and electrically connected to the substrate, forming a second interface. The first interface is separated from the second interface by at least two heterojunctions formed in the substrate.

Abstract: The present invention provides a patterned silicon substrate-silicon germanium thin film composite structure comprising a silicon substrate having a patterned structure, a silicon germanium buffer layer positioned on the silicon substrate, a silicon germanium/silicon superlattice layer positioned on the silicon germanium buffer layer and a silicon germanium thin film layer positioned on the silicon germanium/silicon superlattice layer, wherein the silicon germanium/silicon superlattice layer comprises silicon germanium layers and silicon layers which are grown alternately. The present invention also provides a preparation method of the patterned silicon substrate-silicon germanium thin film composite structure of the present invention. The present invention also provides an application of the patterned silicon substrate-silicon germanium thin film composite structure of the present invention in strained silicon devices.

Abstract: A semiconductor device includes a channel layer, a barrier layer, source contact and a drain contact, a doped group III-V layer, and a gate electrode. The barrier layer is positioned above the channel layer. The source contact and the drain contact are positioned above the barrier layer. The doped group III-V layer is positioned above the barrier layer and between the first drain contact and the first source contact. The first doped group III-V layer has a first non-vertical sidewall and a second non-vertical sidewall. The gate electrode is positioned above the doped group III-V layer and has a third non-vertical sidewall and a fourth non-vertical sidewall. A horizontal distance from the first non-vertical sidewall to the third non-vertical sidewall is different than a horizontal distance from the second non-vertical sidewall to the fourth non-vertical sidewall.

Abstract: In some examples, a transistor comprises a gallium nitride (GaN) layer; a GaN-based alloy layer having a top side and disposed on the GaN layer, wherein source, drain, and gate contact structures are supported by the GaN layer; and a first doped region positioned in a drain access region and extending from the top side into the GaN layer.

Abstract: A method of fabricating a gate with a mini field plate includes forming a dielectric passivation layer over an epitaxy layer on a substrate, coating the dielectric passivation layer with a first resist layer, etching the first resist layer and the dielectric passivation layer to form a first opening in the dielectric passivation layer, removing the first resist layer; and forming a tri-layer gate having a gate foot in the first opening, the gate foot having a first width, a gate neck extending from the gate foot and extending for a length over the dielectric passivation layer on both sides of the first opening, the gate neck having a second width wider than the first width of the gate foot, and a gate head extending from the gate neck, the gate head having a third width wider than the second width of the gate neck.

Abstract: Various embodiments of the present disclosure are directed toward an integrated chip including an undoped layer overlying a substrate. A first barrier layer overlies the undoped layer. A doped layer overlies the first barrier layer. Further, a second barrier layer overlies the first barrier layer, where the second barrier layer is laterally offset from a perimeter of the doped layer by a non-zero distance. The first and second barrier layers comprise a same III-V semiconductor material. A first atomic percentage of a first element within the first barrier layer is less than a second atomic percentage of the first element within the second barrier layer.

Abstract: An N-polar III-N high-electron mobility transistor device can include a III-N channel layer over an N-face of a III-N backbarrier, wherein a compositional difference between the channel layer and the backbarrier causes a 2DEG channel to be induced in the III-N channel layer adjacent to the interface between the III-N channel layer and the backbarrier. The device can further include a p-type III-N layer over the III-N channel layer and a thick III-N cap layer over the p-type III-N layer. The III-N cap layer can cause an increase in the charge density of the 2DEG channel directly below the cap layer, and the p-type III-N layer can serve to prevent a parasitic 2DEG from forming in the III-N cap layer.

Abstract: Disclosed herein are IC structures, packages, and device assemblies with III-N transistors that include additional materials, referred to herein as “stressor materials,” which may be selectively provided over portions of polarization materials to locally increase or decrease the strain in the polarization material. Providing a compressive stressor material may decrease the tensile stress imposed by the polarization material on the underlying portion of the III-N semiconductor material, thereby decreasing the two-dimensional electron gas (2DEG) and increasing a threshold voltage of a transistor. On the other hand, providing a tensile stressor material may increase the tensile stress imposed by the polarization material, thereby increasing the 2DEG and decreasing the threshold voltage. Providing suitable stressor materials enables easier and more accurate control of threshold voltage compared to only relying on polarization material recess.

Abstract: According to claim 1, the invention relates to a method for providing at least one solid-body layer (4). The solid-body layer (4) is separated from a solid body (1).

Abstract: Some embodiments include an integrated assembly having a semiconductor material with a more-doped region adjacent to a less-doped region. A two-dimensional material is between the more-doped region and a portion of the less-doped region. Some embodiments include an integrated assembly which contains a semiconductor material, a metal-containing material over the semiconductor material, and a two-dimensional material between a portion of the semiconductor material and the metal-containing material. Some embodiments include a transistor having a first source/drain region, a second source/drain region, a channel region between the first and second source/drain regions, and a two-dimensional material between the channel region and the first source/drain region.

Abstract: Disclosed are a transistor and a method for forming the transistor. The method includes concurrently forming gate and source/drain openings through an uppermost layer (i.e., a dielectric layer) in a stack of layers. The method can further include: depositing and patterning gate conductor material so that a first gate section is in the gate opening and a second gate section is above the gate opening and so that the source/drain openings are exposed; extending the depth of the source/drain openings; and depositing and patterning source/drain conductor material so that a first source/drain section is in each source/drain opening and a second source/drain section is above each source/drain opening. Alternatively, the method can include: forming a plug in the gate opening and sidewall spacers in the source/drain openings; extending the depth of source/drain openings; depositing and patterning the source/drain conductor material; and subsequently depositing and patterning the gate conductor material.

Abstract: An optoelectronic or electronic device structure, including an active region on or above a polar substrate, wherein the active region comprises a polar p region. The device structure further includes a hole supply region on or above the active region. Holes in the hole supply region are driven by a field into the active region, the field arising at least in part due to a piezoelectric and/or spontaneous polarization field generated by a composition and grading of the active region.

Abstract: A high-electron mobility transistor includes a substrate; a channel layer on the substrate; a AlGaN layer on the channel layer; and a P—GaN gate on the AlGaN layer. The AlGaN layer comprises a first region and a second region. The first region has a composition that is different from that of the second region.

Abstract: A semiconductor device includes a substrate, a channel layer, a barrier layer, a compound semiconductor layer, a source/drain pair, a fluorinated region, and a gate. The channel layer is disposed over the substrate. The barrier layer is disposed over the channel layer. The compound semiconductor layer is disposed over the barrier layer. The source/drain pair is disposed over the substrate, wherein the source and the drain are located on opposite sides of the compound semiconductor layer. The fluorinated region is disposed in the compound semiconductor layer. The gate is disposed on the compound semiconductor layer.

Abstract: A field effect transistor, comprising a gate contact and gate metal forming a vertical structure, such vertical structure having sides and a top surrounded by an air gap formed between a source electrode and a drain electrode of the field effect transistor.

Abstract: The current disclosure describes a vertical tunnel FET device including a vertical P-I-N heterojunction structure of a P-doped nanowire gallium nitride source/drain, an intrinsic InN layer, and an N-doped nanowire gallium nitride source/drain. A high-K dielectric layer and a metal gate wrap around the intrinsic InN layer.

Abstract: A heterojunction semiconductor device comprises a substrate; a second barrier layer is disposed on the second channel layer and a second channel is formed; a trench gate structure is disposed in the second barrier layer; the trench gate structure is embedded into the second barrier layer and is composed of a gate medium and a gate metal located in the gate medium; an isolation layer is disposed in the second channel layer and separates the second channel layer into an upper layer and a lower layer; a first barrier layer is disposed between the lower layer of the second channel layer and the first channel layer and a first channel is formed; a bottom of the metal drain is flush with a bottom of the first barrier layer; and a first metal source is disposed between the second metal source and the first channel layer.

Abstract: A method for forming the semiconductor device that includes forming an etch mask covering a drain side of the gate structure and the silicon containing fin structure; etching a source side of the silicon containing fin structure adjacent to the channel region; and forming a germanium containing semiconductor material on an etched sidewall of the silicon containing fin structure adjacent to the channel region. Germanium from the germanium containing semiconductor material is diffused into the channel region to provide a graded silicon germanium region in the channel region having germanium present at a highest concentration in the channel region at the source end of the channel region and a germanium deficient concentration at the drain end of the channel region.

Abstract: A device includes an NMOS FinFET device including a first fin. The first fin includes a first strain relaxed buffer layer doped with carbon and a first channel semiconductor material formed above the carbon-doped strain relaxed buffer layer. A PMOS FinFET device includes a second fin. The second fin includes a second strain relaxed buffer layer and a second channel semiconductor material formed above the carbon-doped strain relaxed buffer layer. A first gate structure is positioned around a portion of the NMOS fin. A second gate structure is positioned around a portion of the PMOS fin.

Abstract: In one aspect, a method of forming a multiple VT device structure includes the steps of: forming an alternating series of channel and barrier layers as a stack having at least one first channel layer, at least one first barrier layer, and at least one second channel layer; defining at least one first and at least one second active area in the stack; selectively removing the at least one first channel/barrier layers from the at least one second active area, such that the at least one first channel layer and the at least one second channel layer are the top-most layers in the stack in the at least one first and the at least one second active areas, respectively, wherein the at least one first barrier layer is configured to confine charge carriers to the at least one first channel layer in the first active area.

Abstract: In one aspect, a method of forming a multiple VT device structure includes the steps of: forming an alternating series of channel and barrier layers as a stack having at least one first channel layer, at least one first barrier layer, and at least one second channel layer; defining at least one first and at least one second active area in the stack; selectively removing the at least one first channel/barrier layers from the at least one second active area, such that the at least one first channel layer and the at least one second channel layer are the top-most layers in the stack in the at least one first and the at least one second active areas, respectively, wherein the at least one first barrier layer is configured to confine charge carriers to the at least one first channel layer in the first active area.

Abstract: According to one embodiment, a semiconductor device including: a substrate; a gate electrode formed above the substrate; a gate insulating film formed under the gate electrode; a channel layer formed under the gate insulating film by using a channel layer material; a source region and a drain region formed in the substrate so as to interpose the channel layer therebetween in a channel direction; and a source extension layer formed in the substrate between the channel layer and the source region so as to overlap a source-side end portion of the channel layer. The source extension layer forms a heterointerface with the channel layer. The heterointerface is a tunnel channel for carries.

Abstract: A method for manufacturing a compound semiconductor device so as to separate a first substrate from a compound semiconductor laminated structure which includes forming a first compound semiconductor layer over a first substrate containing AlxGa1-xN (0?x<1) and having a first band gap; forming a second compound semiconductor layer over the first compound semiconductor layer containing AlyInzGa1-y-zN (0<y<1, 0<y+z?1) and having a second band gap larger than the first band gap; forming a compound semiconductor laminated structure over the second compound semiconductor layer; and removing the first compound semiconductor layer while irradiating the first compound semiconductor layer with light having an energy between the first band gap and the second band gap, and thereby separating the first substrate from the compound semiconductor laminated structure.

Abstract: In a method for fabricating a graphene structure, there is formed on a fabrication substrate a pattern of a plurality of distinct graphene catalyst materials. In one graphene synthesis step, different numbers of graphene layers are formed on the catalyst materials in the formed pattern. In a method for fabricating a graphene transistor, on a fabrication substrate at least one graphene catalyst material is provided at a substrate region specified for synthesizing a graphene transistor channel and at least one graphene catalyst material is provided at a substrate region specified for synthesizing a graphene transistor source, and at a substrate region specified for synthesizing a graphene transistor drain. Then in one graphene synthesis step, at least one layer of graphene is formed at the substrate region for the graphene transistor channel, and at the regions for the transistor source and drain there are formed a plurality of layers of graphene.

Abstract: A III-N device is described with a III-N material layer, an insulator layer on a surface of the III-N material layer, an etch stop layer on an opposite side of the insulator layer from the III-N material layer, and an electrode defining layer on an opposite side of the etch stop layer from the insulator layer. A recess is formed in the electrode defining layer. An electrode is formed in the recess. The insulator can have a precisely controlled thickness, particularly between the electrode and III-N material layer.