A method for manufacturing a semiconductor structure is provided. The method includes a III-V semiconductor device in a first region of a base substrate and a further device in a second region of the base substrate. The method includes: (a) obtaining a base substrate comprising the first region and the second region, different from the first region; (b) providing a buffer layer over a surface of the base substrate at least in the first region, wherein the buffer layer comprises at least one monolayer of a first two-dimensional layered crystal material; (c) forming, over the buffer layer in the first region, and not in the second region, a III-V semiconductor material; and (d) forming, in the second region, at least part of the further device. A semiconductor structure is also provided.

A method of manufacturing nitride semiconductor substrate, comprising: providing silicon-on-insulator substrate which comprises an underlying silicon layer, a buried silicon dioxide layer and a top silicon layer; forming a first nitride semiconductor layer on the top silicon layer; forming, in the first nitride semiconductor layer, a plurality of notches which expose the top silicon layer; removing the top silicon layer and forming a plurality of protrusions and a plurality of recesses on an upper surface of the buried silicon dioxide layer, wherein each of the plurality of protrusions is in contact with the first nitride semiconductor layer, and there is a gap between each of the plurality of recesses and the first nitride semiconductor layer; and epitaxially growing a second nitride semiconductor layer on the first nitride semiconductor layer, such that the first nitride semiconductor layer and the second nitride semiconductor layer form a nitride semiconductor substrate.

A heterostructure, includes: a substrate; and a buffer layer that includes a plurality of layers having a composition Al.sub.xIn.sub.yGa.sub.1-x-yN, where x≤1 and y≥0; wherein the buffer layer has a first region that includes at least two layers, a second region that includes at least two layers, and a third region that includes at least two layers.

A high electron mobility transistor includes: a first semiconductor layer over a substrate, and a second semiconductor layer over the first semiconductor layer, the second semiconductor layer having a band gap discontinuity with the first semiconductor layer, and at the first semiconductor layer and/or the second conductive layer includes indium. A top layer is over the second semiconductor layer, and a metal layer is over, and extends into, the top layer, the top layer separating the metal layer from the second semiconductor layer. A gate electrode is over the top layer, a third semiconductor layer being between the gate electrode and the top layer, where a sidewall of the third semiconductor layer and a sidewall of the metal layer are separated. A source and drain are on opposite sides of the gate electrode, the top layer extending continuously from below the source, below the gate electrode, and below the drain.

A compound semiconductor has a high electron concentration of 5×10.sup.19 cm.sup.−3 or higher, exhibits an electron mobility of 46 cm.sup.2/V.Math.s or higher, and exhibits a low electric resistance, and thus is usable to produce a high performance semiconductor device. The present invention provides a group 13 nitride semiconductor of n-type conductivity that may be formed as a film on a substrate having a large area size at a temperature of room temperature to 700° C.

A device includes a diode that includes a first group III-nitride (III-N) material and a transistor adjacent to the diode, where the transistor includes the first III-N material. The diode includes a second III-N material, a third III-N material between the first III-N material and the second III-N material, a first terminal including a metal in contact with the third III-N material, a second terminal coupled to the first terminal through the first group III-N material. The device further includes a transistor structure, adjacent to the diode structure. The transistor structure includes the first, second, and third III-N materials, a source and drain, a gate electrode and a gate dielectric between the gate electrode and each of the first, second and third III-N materials.

Embodiments are directed to high electron mobility transistor (HEMT) devices and methods. One such HEMT device includes a substrate having a first surface, and first and second heterostructures on the substrate and facing each other. Each of the first and second heterostructures includes a first semiconductor layer on the first surface of the substrate, a second semiconductor layer on the first surface of the substrate, and a two-dimensional electrode gas (2DEG) layer between the first and second semiconductor layers. A doped semiconductor layer is disposed between the first and second heterostructures, and a source contact is disposed on the first heterostructure and the second heterostructure.

There is provided a semiconductor layer structure (100) comprising: a Si substrate (102) having a top surface (104); a first semiconductor layer (110) arranged on said substrate, the first semiconductor layer comprising a plurality of vertical nanowire structures (112) arranged perpendicularly to said top surface of said substrate, the first semiconductor layer comprising AlN; a second semiconductor layer (120) arranged on said first semiconductor layer laterally and vertically enclosing said nanowire structures, the second semiconductor layer comprising Al.sub.xGa.sub.1-xN, wherein 0≤x≤0.95; a third semiconductor layer (130) arranged on said second semiconductor layer, the third semiconductor layer comprising Al.sub.yGa.sub.1-yN, wherein 0≤y≤0.95; and a fourth semiconductor layer (140) arranged on said third semiconductor layer, the fourth semiconductor layer comprising GaN. There is also provided a high-electron-mobility transistor device and methods of producing such structures and devices.

Provided is a polycrystalline ceramic substrate to be bonded to a compound semiconductor substrate with a bonding layer interposed therebetween, wherein at least one of relational expression (1) 0.7<α.sub.1/α.sub.2<0.9 and relational expression (2) 0.7<α.sub.3/α.sub.4<0.9 holds, where α.sub.1 represents a linear expansion coefficient of the polycrystalline ceramic substrate at 30° C. to 300° C. and α.sub.2 represents a linear expansion coefficient of the compound semiconductor substrate at 30° C. to 300° C., and α.sub.3 represents a linear expansion coefficient of the polycrystalline ceramic substrate at 30° C. to 1000° C. and α.sub.4 represents a linear expansion coefficient of the compound semiconductor substrate at 30° C. to 1000° C.

Disclosed herein are a method of forming a transition metal dichalcogenide thin film and a method of manufacturing a device including the same. The method of forming a transition metal dichalcogenide thin film includes: providing a substrate in a reaction chamber; depositing a transition metal dichalcogenide thin film on the substrate using a sputtering process that uses a transition metal precursor and a chalcogen precursor and is performed at a first temperature; and injecting the chalcogen precursor in a gas state and heat-treating the transition metal dichalcogenide thin film at a second temperature that is higher than the first temperature. The substrate may include a sapphire substrate, a silicon oxide (SiO.sub.2) substrate, a nanocrystalline graphene substrate, or a molybdenum disulfide (MoS.sub.2) substrate.