Abstract: The present invention is a nitride semiconductor substrate including a nitride semiconductor thin film formed on a substrate, in which the nitride semiconductor thin film includes a stress-relaxing layer formed on the substrate and a carbon-doped GaN layer formed on the stress-relaxing layer, and the GaN layer includes high carbon concentration layers and a low carbon concentration layer, the low carbon concentration layer being sandwiched between the high carbon concentration layers and having a lower carbon concentration by 75% or more than the high carbon concentration layers. This provides the nitride semiconductor substrate with improved crystallinity without increasing a thickness of a GaN epitaxial layer and without using other special materials, and a method for producing the substrate.

Abstract: The present invention is a nitride semiconductor substrate including a group III-nitride semiconductor layer containing GaN and formed on a support substrate, in which the support substrate includes: a composite substrate having laminated layers, the laminated layers including a polycrystalline ceramic core, a first adhesive layer bonded entirely to the polycrystalline ceramic core, a second adhesive layer laminated entirely to the first adhesive layer, and a barrier layer bonded entirely to the second adhesive layer; and a group III-nitride semiconductor seed crystal layer containing at least GaN, bonded on the composite substrate via a planarization layer, in which the group III-nitride semiconductor layer is formed on the group III-nitride semiconductor seed crystal layer, and crystallinity on a (0002) growth surface of GaN in the group III-nitride semiconductor seed crystal layer is 550 arcsec or less in XRD half-value width.

Abstract: A substrate for an electronic device, including a nitride semiconductor film formed on a bonded substrate of a silicon single crystal, in which the bonded substrate is a substrate including a first silicon single-crystal substrate having a crystal plane orientation of {111} and a second silicon single-crystal substrate having a crystal plane orientation of {100} being bonded via an oxide film, the first substrate is formed with a notch in <110> direction, the second substrate is formed with a notch in <011> direction or <001> direction, the <110> direction of the first substrate and the <011> direction of the second substrate are bonded in an angular range of ?15° to 15°, and the nitride semiconductor film is formed on a surface of the first substrate of the bonded substrate.

Abstract: The present invention is a nitride semiconductor substrate for high frequency, which includes an SOI substrate in which a single crystal silicon thin film is formed on a single crystal silicon substrate via a silicon oxide layer, and a nitride semiconductor layer including a GaN layer formed on the SOI substrate; in which the single crystal silicon thin film contains nitrogen at a concentration of 2.0×1014 atoms/cm3 or more and has a resistivity of 100 ?cm or more, the single crystal silicon substrate has a resistivity of 50 m?cm or less, and the silicon oxide layer has a thickness of 10 to 400 nm. This can provide the nitride semiconductor substrate in which the nitride semiconductor layer is grown on the SOI substrate for manufacturing devices for high frequency, and the nitride semiconductor substrate with suppressed plastic deformation.

Abstract: A method for manufacturing a nitride semiconductor wafer in which a nitride semiconductor film is formed on a silicon single-crystal substrate includes: a step of forming the nitride semiconductor film on the silicon single-crystal substrate; and a step of irradiating the silicon single-crystal substrate with electron beam so that the silicon single-crystal substrate has a higher resistivity than a resistivity before the irradiation, wherein a substrate doped with nitrogen at a concentration of 5×1014 atoms/cm3 or more and 5×1016 atoms/cm3 or less is used as the silicon single-crystal substrate. A method for manufacturing a nitride semiconductor wafer having a nitride semiconductor film grown on a silicon single-crystal substrate, wherein the method makes it possible that a silicon single-crystal substrate having been irradiated with electron beam and thereby has an increased resistivity is prevented from recovering and having a lower resistivity during the epitaxial growth or other thermal treatment steps.

Abstract: A nitride semiconductor substrate including a growth substrate, and a nitride semiconductor thin film formed on the growth substrate, in which the nitride semiconductor thin film includes an AlN layer formed on the growth substrate and a nitride semiconductor layer formed on the AlN layer, and an average concentration of Y (Yttrium) in the AlN layer is 1E15 atoms/cm3 or higher and 5E19 atoms/cm3 or lower. Thereby, a nitride semiconductor substrate is capable of improving the surface morphology of an AlN layer, thereby suppressing the generation of pits on the surface of a nitride semiconductor epitaxial wafer, and a method manufactures the nitride semiconductor substrate.

Abstract: A nitride semiconductor substrate in which a nitride semiconductor thin film is formed on a substrate for film formation made of single-crystal silicon, in which a silicon nitride film is formed on an peripheral portion of the substrate for film formation, an AlN film is formed on the substrate for film formation and on the silicon nitride film, and the nitride semiconductor thin film is formed on the AlN film. A nitride semiconductor substrate without a reaction mark or a polycrystal growth portion on an edge portion when an AlN layer is epitaxially grown on a silicon substrate, and a GaN or AlGaN layers are epitaxially grown on top of that; and a method for manufacturing the nitride semiconductor substrate.

Abstract: A method for manufacturing a nitride semiconductor substrate in which a nitride semiconductor is formed on a substrate for film formation includes: (1) subjecting a substrate for film formation made of single-crystal silicon to heat treatment under a nitrogen atmosphere to form a silicon nitride film on the substrate for film formation, (2) growing an AlN film on the silicon nitride film, and (3) growing a GaN film, an AlGaN film, or both on the AlN film. A method for manufacturing a nitride semiconductor substrate can prevent diffusion of Al to the high-resistance single-crystal silicon substrate when the AlN layer is epitaxially grown on the high-resistance single-crystal silicon substrate, and the GaN or the AlGaN layer is epitaxially grown on top of that.

Abstract: A nitride semiconductor substrate includes: a silicon single-crystal substrate; and a nitride semiconductor thin film formed on the silicon single-crystal substrate, wherein the silicon single-crystal substrate has a carbon concentration of 5E16 atoms/cm3 or more and 2E17 atoms/cm3 or less. This provides a nitride semiconductor substrate resistant against plastic deformation and a manufacturing method therefor.

Abstract: A nitride semiconductor substrate including: a composite substrate with multiple layers stacked, a silicon oxide layer or a TEOS layer having a central flat surface and a side surface around the flat surface and stacked on the composite substrate; a single crystal silicon layer stacked on the silicon oxide layer or the TEOS layer, and a nitride semiconductor thin film deposited on the single crystal silicon layer, wherein the entire central flat surface of the silicon oxide layer or the TEOS layer is covered with the single crystal silicon layer.

Abstract: The present invention is a substrate for a semiconductor device, including: a high-resistant silicon single crystal substrate having a resistivity of 100 ?·cm or more; a first buffer layer composed of an AlN layer and formed on the high-resistant silicon single crystal substrate; and a nitride semiconductor layer provided on the first buffer layer, wherein there is no low-resistivity portion on a top surface of the high-resistant silicon single crystal substrate, the low-resistivity portion having a resistivity relatively lower than the resistivity of an entirety of the high-resistant silicon single crystal substrate. This provides: a substrate for a semiconductor device that can impart good electric characteristics to a device; and a simple method for manufacturing such a substrate.

Abstract: A nitride semiconductor substrate, including a Ga-containing nitride semiconductor thin film formed on a substrate for film-forming in which a single crystal silicon layer is formed on a composite substrate in which a plurality of layers is bonded, wherein the nitride semiconductor substrate has a region where the Ga-containing nitride semiconductor thin film is not formed inward from an edge of the single crystal silicon layer being a growth surface of the nitride semiconductor thin film. This provides: a nitride semiconductor substrate with inhibited generation of a reaction mark; and a manufacturing method therefor.

Abstract: A wafer marking method uses a laser for performing a laser marking on a defect region of a nitride semiconductor substrate in which a nitride semiconductor layer contains at least a GaN layer formed by epitaxial growth on a single-crystal silicon substrate. The method includes that a surface of the GaN layer and a surface of the single-crystal silicon substrate are performed laser marking simultaneously by irradiating the defect region with a laser of a wavelength within ±10% of 365 nm, having a wavelength corresponding to a band gap energy of GaN.

Abstract: A method for producing a nitride semiconductor wafer by forming a nitride semiconductor film on a silicon single-crystal substrate, including the steps of forming the nitride semiconductor film on the silicon single-crystal substrate and irradiating the silicon single-crystal substrate with electron beams with an irradiation dose of 1×1014/cm2 or more. A method produces a nitride semiconductor wafer in which a nitride semiconductor film is formed on a silicon single-crystal substrate, and in which a loss and a second harmonic characteristic due to the substrate are improved.

Abstract: A nitride semiconductor substrate, including a Ga-containing nitride semiconductor thin film formed on a substrate for film-forming in which a single crystal silicon layer is formed above a supporting substrate via an insulative layer, wherein the nitride semiconductor substrate has a region where the Ga-containing nitride semiconductor thin film is not formed inward from an edge of the single crystal silicon layer being a growth surface of the nitride semiconductor thin film. This provides: a nitride semiconductor substrate with inhibited generation of a reaction mark; and a manufacturing method therefor.

Abstract: A method for producing a nitride semiconductor wafer, in which a nitride semiconductor thin film is grown on a silicon single crystal substrate by vapor phase growth, includes, by using a silicon single crystal substrate having a resistivity of 1000 ?·cm or more, an oxygen concentration of less than 1×1017 atoms/cm3 and a thickness of 1000 ?m or more, growing the nitride semiconductor thin film on the silicon single crystal substrate by vapor phase growth. As a result, a method produces a nitride semiconductor wafer in which plastic deformation and warpage are suppressed even in the case of a high-resistivity, ultra-low oxygen concentration silicon single crystal substrate, which is promising as a support substrate for high frequency devices.

Abstract: A substrate for an electronic device, including a nitride semiconductor film formed on a joined substrate including a silicon single crystal, where the joined substrate has a plurality of silicon single crystal substrates that are joined and has a thickness of more than 2000 ?m, and the plurality of silicon single crystal substrates are produced by a CZ method and have a resistivity of 0.1 ?cm or lower. This provides: a substrate for an electronic device having a nitride semiconductor film formed on a silicon substrate, where the substrate for an electronic device can suppress a warp and can also be used for a product with a high breakdown voltage; and a method for producing the same.

Abstract: The present invention is a substrate for an electronic device, including a nitride semiconductor film formed on a joined substrate including a silicon single crystal, where the joined substrate has at least a bond wafer including a silicon single crystal joined on a base wafer including a silicon single crystal, the base wafer includes CZ silicon having a resistivity of 0.1 ?cm or lower and a crystal orientation of <100>, and the bond wafer has a crystal orientation of <111>. This provides a substrate for an electronic device, having a suppressed warp.

Abstract: A substrate for an electronic device, including a nitride semiconductor film formed on a joined substrate including a silicon single crystal, where the joined substrate has a plurality of silicon single crystal substrates that are joined and has a thickness of more than 2000 ?m, and the plurality of silicon single crystal substrates are produced by a CZ method and have a resistivity of 0.1 ?cm or lower. This provides: a substrate for an electronic device having a nitride semiconductor film formed on a silicon substrate, where the substrate for an electronic device can suppress a warp and can also be used for a product with a high breakdown voltage; and a method for producing the same.

Abstract: A method for manufacturing an epitaxial wafer including the steps of: preparing a silicon-based substrate having a chamfered portion in a peripheral portion; forming an annular trench in the chamfered portion of the silicon-based substrate along an internal periphery of the chamfered portion; and performing an epitaxial growth on the silicon-based substrate having the trench formed. This provides a method for manufacturing an epitaxial wafer by which a crack generated in a peripheral chamfered portion can be suppressed from extending towards the center.