Abstract: A carbon/carbon brake disk is provided. The carbon/carbon brake disk may comprise a carbon fiber, wherein the carbon fiber is formed into a fibrous network, wherein the fibrous network comprises carbon deposited therein. The carbon fiber may undergo a FHT process, wherein micro-cracks are disposed in the carbon fiber. In various embodiments, the micro-cracks may be at least partially filled with un-heat-treated carbon via a final CVD process, wherein the final CVD process is performed at a temperature in the range of up to about 1,000° C. (1,832° F.) for a duration in the range from about 20 hours to about 100 hours. In various embodiments, the un-heat-treated carbon may be configured to prevent oxygen, moisture, and/or oxidation protection systems (OPS) chemicals from penetrating the carbon/carbon brake disk. In various embodiments, the final CVI/CVD process may be configured to increase the wear life of the carbon/carbon brake disk.

Abstract: A method of manufacturing a MXene nanosheet includes removing an A atomic layer from an inorganic compound having a formula of Mn+1AXn to form a nanosheet, the nanosheet having a formula of Mn+1XnTs, and reducing the nanosheet having a formula of Mn+1XnTs to form an MXene nanosheet, the MXene nanosheet having a formula of Mn+1Xn, wherein M is at least one of Group 3 transition metal, Group 4 transition metal, Group 5 transition metal, and Group 6 transition metal, A is at least one of a Group 12 element, Group 13 element, Group 14 element, Group 15 element and Group 16 element, X is one of carbon (C), nitrogen (N) and a combination thereof, Ts is one of oxide (O), epoxide, hydroxide (OH), alkoxide having 1-5 carbon atoms, fluoride (F), chloride (Cl), bromide (Br), iodide (I), and a combination thereof, and n is one of 1, 2 and 3.

Abstract: A method of fabricating a graphite composite structure includes the following steps. An amorphous carbon layer having a short-range ordered structure region in a range from 50% to 100% is provided. At least one force is locally applied on a surface of the amorphous carbon layer to form at least one stressed region. An annealing process is performed on the amorphous carbon layer so as to form at least one long-range ordered graphite structure in the at least one stressed region. The at least one long-range ordered graphite structure includes a stack structure including a plurality of (002) planes. An angle between an extension direction of the (002) planes and the surface of the amorphous carbon layer is in a range from 45 degrees or more to 90 degrees or less.

Abstract: [Object] The present invention provides a friction material used for a disc brake pad, which is manufactured by forming a non-asbestos-organic (NAO) friction material composition that does not contain a copper component, which provides an excellent wear resistance and a highly stable braking effectiveness even after being subjected to a history of high temperatures and high loads. [Means to Resolve] The friction material composition for the friction material molding containing, as an inorganic friction modifier, 10-40 weight % of a monoclinic zirconium oxide with an average particle diameter of 1-8 ?m relative to the total amount of the friction material composition, 1.

Abstract: A heat dissipation structure comprises a flexible substrate, a graphite sheet, and a heat insulating material. The flexible substrate comprises a first surface and a second surface facing away from the first surface. The graphite sheet is connected to the second surface. At least one containing cavity is defined on an interface between the second surface and the graphite sheet. The heat insulating material is filled in the at least one containing cavity to form a heat insulating structure.

Abstract: A method of forming an epitaxial layer on a substrate such as a sapphire wafer that does not readily absorb thermal radiation. The method includes coating a first side surface of the substrate with an energy-absorbing opaque material. The opaque material forms a thermally absorptive coating on the substrate. The coated substrate may be heated to remove contaminants from the thermally absorptive coating. The coated substrate is positioned in a vacuum deposition chamber and heated by directing radiative energy onto the thermally absorptive coating. An epitaxial layer such as GaN or SiGe is formed on a second side surface of the substrate opposite the thermally absorptive coating.

Abstract: A composite diamond body includes a diamond base material and a stable layer disposed on the diamond base material. The stable layer may have a thickness of 0.001 ?m or more and less than 10 ?m, and may include a plurality of layers. A composite diamond tool includes the composite diamond body. There are thus provided highly wear-resistant composite diamond body and composite diamond tool that are even applicable to mirror-finish planarization of a workpiece which reacts with diamond to cause the diamond to wear.

Abstract: A method for making patterned two dimensional (2D) transition metal dichalcogenides (TMDs) nanomaterials is disclosed. The method includes making a substrate, wherein the substrate has a substrate surface including a first portion surface and a second portion surface, the first portion surface is formed by oxide or nitride, and the second portion surface is formed by mica; applying a mono 2D TMDs nanomaterials; annealing the mono 2D TMDs nanomaterials and the substrate in an oxygen containing gas, the annealing temperature is controlled so that only the part of the 2D TMDs nanomaterials, that is on the second portion surface, is removed by oxidization, and the other part of the 2D TMDs nanomaterials, that is on the first portion surface, is remained to form the patterned 2D TMDs nanomaterials.

Abstract: A porous electrode substrate has a form of a tape material and contains a structure made of carbon fibers and a carbon matrix. A specific surface area, porosity, and pore distribution are determined by the carbon matrix. The carbon matrix contains carbon particles including activated carbon with a high specific surface area and a carbonized or graphitized residue of a carbonizable or graphitizable binder.

Abstract: A member for a semiconductor manufacturing apparatus according to the present invention is a member that is to be joined to an aluminum nitride base member. The member is composed of a composite material including principal constituent phases that are aluminum nitride and a pseudopolymorph of aluminum nitride which includes silicon, aluminum, oxygen, and nitrogen. The pseudopolymorph of aluminum nitride has at least one periodic structure selected from a 27R phase and a 21R phase or an X-ray diffraction peak at least at 2?=59.8° to 60.8°. The composite material has a thermal conductivity of 50 W/mK or less at room temperature.

Abstract: To provide a piston ring comprising a hard carbon film that is easy to form and exhibits excellent wear resistance. The above-described problem is solved by having a hard carbon film 4 formed on at least an outer peripheral sliding surface 11 of a piston ring base material 1, wherein the hard carbon film 4 is a laminated film comprising a plurality of layers, and is configured so as to contain boron within a range of an atomic density of 0.2×1022 atoms/cm3 to 2.0×1022 atoms/cm3 inclusive. This hard carbon film 4 may be configured to have an sp2 component ratio within a range of 40% to 80% inclusive, measured in a TEM-EELS spectrum formed by combining electron energy loss spectroscopy (EELS) with a transmission electron microscope (TEM), and a hydrogen content within a range of 0.1 atom % to 5 atom % inclusive. Further, a total thickness of this hard carbon film 4 may be configured to be within a range of 0.5 ?m to 20 ?m inclusive.

Abstract: A material including a transparent substrate coated with a stack acting on infrared radiation includes at least one functional layer and at least one upper protective layer deposited above at least a part of the functional layer. The upper protective layer is a hydrogenated carbon layer, within which layer the carbon atoms form carbon-carbon and carbon-hydrogen bonds and are essentially in an sp2 hybridization state.

Abstract: A structural composite component, in particular for an aircraft or spacecraft, has a lightning strike protection layer, and a composite battery comprising a cathode layer, wherein the lighting strike protection layer is formed integrated with the cathode layer.

Abstract: The invention relates to a coated body and to a method for coating a body. The coated body comprises at least a substrate (22), a diamond layer (24) having a thickness of 1-40 ?m, and a hard material layer (26), which is arranged farther outside on the body (10) than the diamond layer (24). The hard material layer (26) comprises at least one metal element and at least one non-metal element. An adhesive layer (32) having a thickness of 2-80 nm is provided between the diamond layer (24) and the hard material layer (26). The adhesive layer (32) contains carbon and at least one metal element. The diamond layer (24) can be applied by means of a CVD method. The hard material layer can be applied by means of a PVD method.

Abstract: A method for manufacturing a separator for fuel cell including a seal part of thermosetting resin can have improved productivity. The method includes a placing step to place uncured thermosetting resin on a substrate, a pre-curing step to pre-cure the uncured thermosetting resin on the substrate, and a curing step to cure the pre-cured thermosetting resin on the collected plurality of substrates to collectively form the seal parts on the plurality of substrates.

Abstract: A heat-dissipating sheet having a density of 1.9 g/cm3 or more and an in-plane thermal conductivity of 570 W/mK or more, which comprises carbon black uniformly dispersed among fine graphite particles, a mass ratio of fine graphite particles to carbon black being 75/25 to 95/5, is obtained by repeating plural times a cycle of applying a dispersion of fine graphite particles, carbon black and an organic binder in an organic solvent to a surface of a support plate, and then drying it, to form a resin-containing composite sheet; burning the resin-containing composite sheet to remove the organic binder; and pressing the resultant composite sheet of fine graphite particles and carbon black for densification.

Abstract: Provided is an electrode mixture layer capable of reducing internal resistance by use of a carbon nanotube molding. The electrode mixture layer includes an active material and a conductor of carbon nanotubes in close contact with the surface of the active material, and the number density of the carbon nanotubes is 4 tubes/?m or more. The number density is defined as a value obtained by providing measurement lines on a scanning electron microscope image of a surface of the electrode mixture layer at 0.3 ?m intervals both longitudinally and laterally, measuring the total number of the carbon nanotubes being in close contact with the surface of the active material and intersecting the measurement lines, and dividing the total number of the carbon nanotubes by the total length of the measurement lines on the active material surface.

Abstract: To provide a piston ring comprising a hard carbon film that is easy to form and exhibits excellent adhesion and wear resistance, and a manufacturing method therefor. The above-described problem is solved by means of a piston ring comprising a hard carbon film 50 formed on at least an outer peripheral sliding surface 11 of a piston ring base material 1, wherein the hard carbon film 50 is a laminated film comprising a plurality of layers, including an upper layer 5 with a lamination pitch within a range of 3 nm to 50 nm inclusive, a middle layer 4 with a lamination pitch less than that of the upper layer 5, and a lower layer 3 with a lamination pitch within the same range as that of the upper layer 5 and greater than that of the middle layer 4.

Abstract: Aligned high quality boron nitride nanotubes (BNNTs) can be incorporated into groups and bundles and placed in electronic and electrical components (ECs) to enhance the heat removal and diminish the heat production. High quality BNNTs are excellent conductors of heat at the nano scale. High quality BNNTs are electrically insulating and can reduce dielectric heating. The BNNTs composite well with a broad range of ceramics, metals, polymers, epoxies and thermal greases thereby providing great flexibility in the design of ECs with improved thermal management. Controlling the alignment of the BNNTs both with respect to each other and the surfaces and layers of the ECs provides the preferred embodiments for ECs.

Abstract: The invention relates to an at least partly stratified (such as at least partly dual stratified) charge combustion engine, especially CAI (combustion assisted ignition), HCC, HCSI and HCCI engine, in which the combustion of a hydrocarbon containing fuel generating a flame emitting photon is operated in a chamber with a wall provided with a cerium oxide-carbon containing coating, said coating further comprising at least comprising oxides of the followings elements Pr, Nd, La and at least Y and/or Zr. The engine of the invention enables a catalytic reduction of NOx exhaust rate.

Abstract: Chemically strengthened glass articles having at least one deep compressive layer extending from a surface of the article to a depth of layer DOL of about 130 ?m up to about 175 ?m or, alternatively, to a depth of compression (DOC) in a range from about 90 ?m to about 120 ?m within the article. The compressive layer has a stress profile that includes a first substantially linear portion extending from a relatively shallow depth to the DOL or DOC and a second portion extending from the surface to the shallow depth. The second portion is substantially linear at a depth from 0 ?m to 5 ?m and has a steeper slope than that of the first portion of the profile. Methods of achieving such stress profiles are also described.

Abstract: Provided is an integrated layer (10 nm to 500 ?m) of highly oriented halogenated graphene having a formula C6ZxOy, wherein Z is a halogen element selected from F, Cl, Br, I, or a combination thereof, x=0.01 to 6.0, y=0 to 5.0, and x+y?6.0. The integrated layer has halogenated graphene crystals having an inter-planar spacing d002 of 0.35 nm to 1.2 nm (more typically 0.4-1.0 nm) as determined by X-ray diffraction. The integrated layer has multiple constituent graphene halide planes that are substantially parallel to one another along one direction having an average deviation angle of these graphene halide planes less than 10 degrees.

Abstract: A catalyst layer for a fuel cell includes a catalyst-supporting carbon in which a catalyst is supported on carbon support powder of which particles have pores, a first electrolyte resin having an oxygen permeability of less than 2.2×10?14 mol/(m·s·Pa) under an environment at a temperature of 80° C. and a relative humidity of 30%, and a second electrolyte resin having an oxygen permeability of 2.2×10?14 mol/(m·s·Pa) or more under an environment at a temperature of 80° C. and a relative humidity of 30%. The content of the first electrolyte resin is an amount equal to or larger than a value X [g] obtained in the equation X=S×R/4436 with respect to 1 g of the carbon support. S denotes a surface area [m2] of the carbon support. R denotes a proportion of the area of the outermost surface of the carbon support with respect to the surface area of the carbon support.

Abstract: An article comprises a carbon fibre reinforced plastic (CFRP) substrate, a buffer layer disposed adjacent the substrate, the buffer layer comprising a poly(para-xylylene) polymer; and a moisture barrier coating disposed adjacent the buffer layer.

Abstract: The invention relates to a reinforcement, containing fibers and resin, for an element made of a composite material, particularly a wind turbine blade, characterized in that said reinforcement is produced by stacking at least two parts produced by pultrusion. A reinforcement, containing fibers and resin, for an element made of a composite material, particularly a wind turbine blade, is characterized in that the reinforcement is produced by stacking at least two parts produced by pultrusion.

Abstract: A film includes a film body including graphite, and at least one fragment including graphite and formed on one or more surfaces of the film body. The film has a water contact angle of 50 degrees or greater and a glossiness of 20 or lower.

Abstract: A nozzle plate includes a nozzle open to one surface of the nozzle plate to eject ink, and a diamond-like carbon (DLC) layer disposed adjacent to the one surface. The DLC layer has surface irregularities including recesses and protrusions. The protrusions adjoining one another have ends to be in contact with the ink. The ends are located at mutually different positions in a direction intersecting the one surface.

Abstract: The present disclosure provides a method for coating a composite structure, comprising applying a single pretreating composition on a surface of the composite structure, the single pretreating composition comprising a first acid aluminum phosphate comprising a molar ratio of aluminum to phosphate between 1 to 2 and 1 to 3, and heating the composite structure to a first temperature sufficient to form an aluminum phosphate polymer layer on the composite structure.

Abstract: A method for production of various morphologies of solid carbon product by reducing carbon oxides with a reducing agent in the presence of a catalyst. The carbon oxides are typically either carbon monoxide or carbon dioxide. The reducing agent is typically either a hydrocarbon gas or hydrogen. The desired morphology of the solid carbon product may be controlled by the specific catalysts, reaction conditions, and optional additives used in the reduction reaction. The resulting solid carbon products have many commercial applications.

Abstract: A polyimide film suitable for use in the fabrication of a graphite layer includes a polyimide derived from reaction of diamine monomers with dianhydride monomers, and a foaming agent incorporated in the polyimide. Moreover, a process of fabricating a graphite film includes providing a polyamic acid solution formed by reaction of diamine monomers with dianhydride monomers, incorporating a foaming agent into the polyamic acid solution, forming a polyimide film from the polyamic acid solution, applying a first thermal treatment so that the polyimide film is carbonized to form a carbon film, and applying a second thermal treatment so that the carbon film is converted to a graphite film.

Abstract: The present invention relates to graphene and, particularly, to a method for doping graphene using substrate surface modification, a method for manufacturing a graphene composite electrode using graphene and inorganic matter, and a graphene structure comprising the same. The method for doping graphene according to an embodiment of the present invention may comprise the steps of: forming, on a substrate, a precursor polymer layer for doping; and positioning graphene on the substrate on which the precursor polymer layer is formed. In addition, the method for manufacturing a graphene composite electrode according to an embodiment of the present invention may comprise the steps of: forming graphene on catalyst metal; forming a transparent conductive oxide on the graphene; crystallizing the transparent conductive oxide by applying heat of 150° C. or higher; and transferring, to a final substrate, a composite electrode consisting of the graphene and the transparent conductive oxide.

Abstract: A method of manufacturing a diamond substrate includes: forming an ion implantation layer at a side of a main surface of a diamond seed substrate by implanting ions into the main surface of the diamond seed substrate; producing a diamond structure by growing a diamond growth layer by a vapor phase synthesis method on the main surface of the diamond seed substrate, after implanting the ions; and performing heat treatment on the diamond structure. The performed heat treatment causes the diamond structure to be separated along the ion implantation layer into a first structure including the diamond seed substrate and failing to include the diamond growth layer, and a diamond substrate including the diamond growth layer. Thus, the method of manufacturing a diamond substrate is provided that enables a diamond substrate with a large area to be manufactured in a short time and at a low cost.

Abstract: Provided are a coating film, a manufacturing method for the same, and a PVD device that not only sufficiently improve the balance of low-friction properties and wear resistance, but also improve chipping resistance and peeling resistance. This film is coated on a substrate surface, wherein the coating film has a hard carbon that presents relatively black and white when observed in a cross-sectional bright-field TEM image, a mesh-shaped hard carbon layer is formed using a PVD method, said layer having white-colored hard carbon in a mesh shape extending in the thickness direction and black-colored hard carbon dispersed into the cavities in the mesh, and the ID/IG ratio is 1-6 when the mesh-shaped hard carbon layer is measured using Raman spectroscopy, said ratio being the ratio of the Raman spectrum D band peak area intensity and G band peak area intensity.

Abstract: A yarn producing apparatus produces carbon nanotube (CNT) yarn by aggregating CNT fibers, A substrate support supports a CNT forming substrate, a winding unit continuously draws the CNT fibers, a yarn producing unit aggregates the CNT fibers, a status monitor monitors a state of the CNT yarn, and a supply state changing mechanism changes a supply state of the CNT fibers, based on a result of monitoring by the status monitor.

Abstract: The present invention provides an attracting tool that is convenient, inexpensive, and useful for hunting. The present invention provides an attracting tool comprising an exothermic composition and an attractant, the exothermic composition containing an oxidation accelerator having an iodine adsorption number of not more than 700 g/kg, an oxidizable metal powder, and water, wherein at least the exothermic composition is housed in an air-permeable container bag.

Abstract: A polycrystalline diamond body, and a method for making a carbonate polycrystalline diamond body includes combining a first quantity of diamond particles with a first quantity of magnesium carbonate to form a first layer in an enclosure, the first layer having a working surface, and placing a second quantity of magnesium carbonate in the enclosure forming a second layer, the first layer and the second layer forming an assembly. A quantity of at least one of silicon or aluminum is mixed in with or placed adjacent to at least one of the first layer or the second layer. The assembly, including the at least one of silicon or aluminum, is sintered at high pressure and high temperature, causing the at least one of silicon or aluminum to infiltrate at least one layer of the assembly, forming a polycrystalline diamond body.

Abstract: A lightweight shield for aircraft protection against threat of high energy impacts, which comprises, a structural layer that has a first side and a second side, the first side being intended for receiving the impact, and a ballistic material layer for absorbing high energy impacts, having a first side and a second side. The first side of the ballistic material layer is faced to the second side of structural layer and joined to the structural layer via a progressively detachable interface and, the second side of the ballistic material layer is a free surface.

Abstract: A textile-reinforced composite friction material is provided by the present invention that includes a nonwoven needlepunched fiber mat, a resin matrix impregnated within and onto the fiber mat, and a carbon nanomaterial dispersed within the resin matrix. The carbon nanomaterial is preferably carbon nanotubes and/or carbon nanofibers.

Abstract: A semiconductor structure having a multiple-porous graphene layer includes a sapphire substrate, a single or multiple layer porous graphene film, and a gallium nitride layer. A fabrication method for forming the semiconductor structure having a single or multiple layer porous graphene film, includes: firstly, growing up the graphene on the copper foil; then, using the acetone and isopropyl alcohol to wash the sapphire substrate, and then using the nitrogen flow to dry up; transferring the graphene onto the semiconductor substrate, using the Poly(methyl methacrylate) to fix the single or multiple layer porous graphene film, and using the acetone to wash up; using the photolithography process to etch the whole surface of the multiple-porous graphene layer; and, using the metalorganic chemical vapor deposition to deposit gallium nitride on the single or multiple layer porous graphene film and the sapphire substrate.

Abstract: A method for functionalizing carbon-based nanomaterials that may include: preparing a first suspension including an electrolyte solution, an amine source, and a plurality of carbon-based nanomaterials that are dispersed in the first suspension; and subjecting the first suspension to an electrochemical reaction by placing the first suspension between two electrodes and applying a voltage between the electrodes for a predetermined amount of time to obtain functionalized carbon-based nanomaterials in a second suspension.

Abstract: An object is to provide a graphite-copper composite electrode material that is capable of reducing electrode wear to a practically usable level and to provide an electrical discharge machining electrode using the material. A graphite-copper composite electrode material includes a substrate comprising a graphite material and having pores, and copper impregnated in the pores of the substrate, the electrode material having an electrical resistivity of 2.5 ??m or less, preferably 1.5 ??m or less, more preferably 1.0 ??m or less. It is desirable that the substrate comprising the graphite material have an anisotropy ratio of 1.2 or less. It is desirable that an impregnation rate ? of the copper in the electrode material is 13% or greater. It is desirable that the substrate comprising the graphite material have a bulk density of from 1.40 Mg/m3 to 1.85 Mg/m3.

Abstract: A composite is obtained by press-molding a mixed powder comprising 20-50 vol % of a metal powder and 50-80 vol % of a diamond powder for which a first peak in a volumetric distribution of particle size lies at 5-25 ?m, and a second peak lies at 55-195 ?m, and a ratio between the area of a volumetric distribution of particle sizes of 1-35 ?m and the area of a volumetric distribution of particle sizes of 45-205 ?m is from 1:9 to 4:6, thereby obtaining a composite having a high thermal conductivity and a coefficient of thermal expansion close to that of semiconductor devices, which is easy to mold into a prescribed shape.

Abstract: The invention relates to a coating which has special absorption properties for electromagnetic radiation from the wavelength spectrum of sunlight and to a method for producing the coating and to its use. The coating is formed by a layer which is formed on the surface of a substrate or on a reflective layer formed on the surface of the substrate. Carbon nanotubes are contained in the layer. The proportion of carbon nanotubes contained per unit of area or unit of volume and/or the layer thickness of the layer is selected such that it absorbs electromagnetic radiation from the wavelength spectrum of sunlight at predefinable proportions and the proportion of electromagnetic radiation from the wavelength spectrum of a black radiator at a temperature greater than 50° C. which is emitted is very small.

Abstract: A graphene structure is provided. The graphene structure includes a two-dimensional base graphene layer having a defect, and a linking material provided at the defect of the base graphene layer.

Abstract: Compositions of matter including a cloth base comprising one or more not fully carbon fibers woven together, where at least a portion of the not fully carbon fibers of the cloth base are carbonized and comprise graphene petals thereon. The not fully carbon fibers may be selected from a variety of materials including cellulose fibers such as hemp, linen, and/or cotton, and may also or alternatively include synthetic fibers such as polyester, Kevlar, and/or Rayon. A method for producing such a carbonized conductive fiber-based cloth is also provided, the method including carbonizing a cloth base comprising not fully carbon fibers in a plasma stream of a plasma process and growing graphene petals integrally on the carbonized cloth using the same plasma process.

Abstract: A belt device includes a belt that is rotatable and a driving rotator to drive and rotate the belt and to be accidentally adhered with a foreign substance. The driving rotator includes a coating layer as a surface layer. The coating layer includes a plurality of fine particles.

Abstract: Disclosed herein is a method for preparing large soluble graphenes. The method comprises attaching one or more hindering groups to the graphene, which can prevent face-to-face graphene stacking by reducing the effects of inter-graphene attraction. The large graphenes can absorb a wide spectrum of light from UV to near infrared, and are useful in photovoltaic devices and sensitizers in nanocrystalline solar cells.

Abstract: The present invention relates to a transferring method of graphene using a self-adhesive film.

Abstract: The present invention provides an OLED device, and a packaging method thereof and a packaging apparatus. The packaging method is for packaging an OLED device formed on a base substrate, and includes: separating a graphene thin film formed on a copper foil from the copper foil; and packaging the OLED device using the graphene thin film. In the packaging method, the graphene thin film is introduced into packaging of an OLED device, thereby not only improving packaging effect of the OLED device, but also simplifying packaging process of the OLED device and increasing production efficiency.

Abstract: A method for producing a diamond single crystal includes implanting an ion other than carbon into a surface of a diamond single crystal seed substrate and thereby decreasing the transmittance of light having a wavelength of 800 nm, the surface having an off-angle of 7 degrees or less with respect to a {100} plane, and homoepitaxially growing a diamond single crystal on the ion-implanted surface of the seed substrate using a chemical vapor synthesis under synthesis conditions where the ratio NC/NH of the number of carbon-containing molecules NC to the number of hydrogen molecules NH in a gas phase is 10% or more and 40% or less, the ratio NN/NC of the number of nitrogen molecules NN to the number of carbon-containing molecules NC in the gas phase is 0.1% or more and 10% or less, and the seed substrate temperature T is 850° C. or more and less than 1000° C.