To provide a gallium oxide-based semiconductor with its bandgap being sufficiently reduced, and a manufacturing method thereof. A gallium oxide-based semiconductor containing a mixed crystal having a composition represented by (Ga.sub.(1-x)Fe.sub.x).sub.2yO.sub.3, wherein 0.10x0.40 and 0.85y1.2, wherein the mixed crystal has a beta-gallia structure, is provided. Also, a method for manufacturing the gallium oxide-based semiconductor, including depositing a mixed crystal having a composition represented by (Ga.sub.(1-x)Fe.sub.x).sub.2yO.sub.3, wherein 0.10x0.40 and 0.85y1.2 on a substrate surface by a pulsed laser deposition method, wherein denoting the temperature of the substrate as T C., x and T satisfy the relationship represented by 500x+800T<1,000, is provided.

The present disclosure provides techniques for epitaxial oxide materials, structures and devices. In some embodiments, the techniques described herein relate to a transistor, including: a substrate including a first oxide material; an epitaxial oxide layer on the substrate including a second oxide material with a first bandgap; a gate layer on the epitaxial oxide layer, the gate layer including a third oxide material with a second bandgap, wherein the second bandgap is wider than the first bandgap; and electrical contacts. The second oxide material can include: one or two of Li, Ni, Al, Ga, Mg, and Zn; Ge; and O. The second oxide can also include (Ni.sub.xMg.sub.yZn.sub.1-x-y).sub.2GeO.sub.4 wherein 0x1 and 0y1. The electrical contacts can include: a source electrical contact coupled to the epitaxial oxide layer; a drain electrical contact coupled to the epitaxial oxide layer; and a first gate electrical contact coupled to the gate layer.

Various forms of Mg.sub.xGe.sub.1?xO.sub.2?x are disclosed, where an epitaxial layer comprises single crystal Mg.sub.xGe.sub.1?xO.sub.2?x, with x having a value of 0?x<1, wherein the single crystal Mg.sub.xGe.sub.1?xO.sub.2?x has a crystal symmetry compatible with a substrate or with an underlying layer on which the single crystal Mg.sub.xGe.sub.1?xO.sub.2?x is grown. Semiconductor structures and devices comprising the epitaxial layer of Mg.sub.xGe.sub.1?xO.sub.2?x are disclosed, along with methods of making the epitaxial layers and semiconductor structures and devices.

A coating liquid for forming an n-type oxide semiconductor film, the coating liquid including: a Group A element, which is at least one selected from the group consisting of Sc, Y, Ln, B, Al, and Ga; a Group B element, which is at least one of In and Tl; a Group C element, which is at least one selected from the group consisting of Group 4 elements, Group 5 elements, Group 6 elements, Group 7 elements, Group 8 elements, Group 9 elements, Group 10 elements, Group 14 elements, Group 15 elements, and Group 16 elements; and a solvent.

The present disclosure provides techniques for epitaxial oxide materials, structures and devices. In some embodiments, an integrated circuit includes a field effect transistor (FET) and a waveguide coupled to the FET, wherein the waveguide comprises a signal conductor. The FET can include: a substrate comprising a first oxide material; an epitaxial semiconductor layer on the substrate, the epitaxial semiconductor layer comprising a second oxide material with a first bandgap; a gate layer on the epitaxial semiconductor layer, the gate layer comprising a third oxide material with a second bandgap, wherein the second bandgap is wider than the first bandgap; and electrical contacts. The electrical contacts can include: a source electrical contact coupled to the epitaxial semiconductor layer; a drain electrical contact coupled to the epitaxial semiconductor layer; and a first gate electrical contact coupled to the gate layer.

A method for preparing a cap-layer-structured gallium oxide field effect transistor, includes: removing a gallium oxide channel layer and a gallium oxide cap layer from a passive area of a gallium oxide epitaxial wafer; respectively removing the gallium oxide cap layer corresponding to a source region of the gallium oxide epitaxial wafer and the gallium oxide cap layer corresponding to a drain region of the gallium oxide epitaxial wafer; respectively doping a portion of the gallium oxide channel layer corresponding to the source region and a portion of the gallium oxide channel layer corresponding to the drain region with an N-type impurity; respectively capping an upper surface of the gallium oxide channel layer corresponding to the source region and an upper surface of the gallium oxide channel layer corresponding to the drain region with a first metal layer to respectively form a source and a drain; and forming a gate.

A novel design for a nitrogen polar high-electron-mobility transistor (HEMT) structure comprising a GaN/InGaN composite channel. As A novel design for a nitrogen polar high-electron-mobility transistor (HEMT) structure comprising a GaN/InGaN composite channel. As illustrated herein, a thin InGaN layer introduced in the channel increases the carrier density, reduces the electric field in the channel, and increases the carrier mobility. The dependence of p on InGaN thickness (.sup.tInGaN) and indium composition (.sup.xIn) was investigated for different channel thicknesses. With optimized .sup.tInGaN and .sup.xIn, significant improvements in electron mobility were observed. For a 6 nm channel HEMT, the electron mobility increased from 606 to 1141 cm.sup.2/(V.Math.s) when the 6 nm thick pure GaN channel was replaced by the 4 nm GaN/2 nm In.sub.0.1Ga.sub.0.9N composite channel.

A thin layer of lattice matched wide bandgap semiconductor material having semi-insulating properties is employed as an isolation layer between the substrate and a vertical stack of suspended semiconductor channel material nanosheets. The presence of such an isolation layer eliminates the parasitic leakage path between the source region and the drain region that typically occurs through the substrate, while not interfering with the CMOS device that is formed around the semiconductor channel material nanosheets.

A film-forming method for heat-treating a raw material solution atomized into a mist and performing a film-formation, and the method includes the following steps: atomizing the raw material solution or making the raw material solution into droplets to generate a mist; conveying the mist to a film-forming part by a carrier gas; and supplying the mist from a nozzle to a substrate, heat-treating the mist on the substrate, and performing the film-formation in the film-forming part, wherein with the area of an opening surface of the nozzle being S [cm.sup.2], the longest distance among distances between points in the opening surface and the surface of the substrate being H [cm], and the flow rate of the carrier gas supplied from the nozzle being Q [L/min], SH/Q?0.015 results.

A film formation device which forms a film on a substrate through the heat treatment of a starting material solution in the form of a mist, the film formation device including a mist conversion unit that generates a mist by converting the starting material solution into mist, a carrier gas supply unit that supplies a carrier gas for transporting the mist generated by the mist conversion unit, a film formation unit that includes therein a placement part for placing the substrate and that is where the mist transported by the carrier gas is supplied onto the substrate, and an exhaust unit that exhausts exhaust gas from the film formation unit, and further including, above the placement part in the film formation unit, a nozzle for supplying the mist onto the substrate and a top plate for adjusting the flow of the mist supplied from the nozzle.