WO2019137944A1 - Procédé de fabrication de carbure de silicium - Google Patents

Procédé de fabrication de carbure de silicium Download PDF

Info

Publication number
WO2019137944A1
WO2019137944A1 PCT/EP2019/050413 EP2019050413W WO2019137944A1 WO 2019137944 A1 WO2019137944 A1 WO 2019137944A1 EP 2019050413 W EP2019050413 W EP 2019050413W WO 2019137944 A1 WO2019137944 A1 WO 2019137944A1
Authority
WO
WIPO (PCT)
Prior art keywords
substrate
temperature
silicon carbide
fibers
educt
Prior art date
Application number
PCT/EP2019/050413
Other languages
German (de)
English (en)
Inventor
Bettina Friedel
Original Assignee
Universität Paderborn
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Universität Paderborn filed Critical Universität Paderborn
Priority to EP19700866.7A priority Critical patent/EP3737646A1/fr
Publication of WO2019137944A1 publication Critical patent/WO2019137944A1/fr

Links

Classifications

    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
    • C01B32/00—Carbon; Compounds thereof
    • C01B32/90—Carbides
    • C01B32/914—Carbides of single elements
    • C01B32/956—Silicon carbide
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
    • C01B32/00—Carbon; Compounds thereof
    • C01B32/90—Carbides
    • C01B32/914—Carbides of single elements
    • C01B32/956—Silicon carbide
    • C01B32/963—Preparation from compounds containing silicon
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B35/00—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
    • C04B35/622—Forming processes; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
    • C04B35/62227—Forming processes; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products obtaining fibres
    • C04B35/62272—Forming processes; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products obtaining fibres based on non-oxide ceramics
    • C04B35/62277—Fibres based on carbides
    • C04B35/62281—Fibres based on carbides based on silicon carbide
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B35/00—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
    • C04B35/622—Forming processes; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
    • C04B35/624—Sol-gel processing
    • C—CHEMISTRY; METALLURGY
    • C30—CRYSTAL GROWTH
    • C30B—SINGLE-CRYSTAL GROWTH; UNIDIRECTIONAL SOLIDIFICATION OF EUTECTIC MATERIAL OR UNIDIRECTIONAL DEMIXING OF EUTECTOID MATERIAL; REFINING BY ZONE-MELTING OF MATERIAL; PRODUCTION OF A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; SINGLE CRYSTALS OR HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; AFTER-TREATMENT OF SINGLE CRYSTALS OR A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; APPARATUS THEREFOR
    • C30B23/00—Single-crystal growth by condensing evaporated or sublimed materials
    • C—CHEMISTRY; METALLURGY
    • C30—CRYSTAL GROWTH
    • C30B—SINGLE-CRYSTAL GROWTH; UNIDIRECTIONAL SOLIDIFICATION OF EUTECTIC MATERIAL OR UNIDIRECTIONAL DEMIXING OF EUTECTOID MATERIAL; REFINING BY ZONE-MELTING OF MATERIAL; PRODUCTION OF A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; SINGLE CRYSTALS OR HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; AFTER-TREATMENT OF SINGLE CRYSTALS OR A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; APPARATUS THEREFOR
    • C30B29/00—Single crystals or homogeneous polycrystalline material with defined structure characterised by the material or by their shape
    • C30B29/10—Inorganic compounds or compositions
    • C30B29/36—Carbides
    • C—CHEMISTRY; METALLURGY
    • C30—CRYSTAL GROWTH
    • C30B—SINGLE-CRYSTAL GROWTH; UNIDIRECTIONAL SOLIDIFICATION OF EUTECTIC MATERIAL OR UNIDIRECTIONAL DEMIXING OF EUTECTOID MATERIAL; REFINING BY ZONE-MELTING OF MATERIAL; PRODUCTION OF A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; SINGLE CRYSTALS OR HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; AFTER-TREATMENT OF SINGLE CRYSTALS OR A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; APPARATUS THEREFOR
    • C30B29/00—Single crystals or homogeneous polycrystalline material with defined structure characterised by the material or by their shape
    • C30B29/60—Single crystals or homogeneous polycrystalline material with defined structure characterised by the material or by their shape characterised by shape
    • C30B29/66—Crystals of complex geometrical shape, e.g. tubes, cylinders
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
    • C01P2004/00—Particle morphology
    • C01P2004/10—Particle morphology extending in one dimension, e.g. needle-like
    • C01P2004/16—Nanowires or nanorods, i.e. solid nanofibres with two nearly equal dimensions between 1-100 nanometer
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
    • C04B2235/65—Aspects relating to heat treatments of ceramic bodies such as green ceramics or pre-sintered ceramics, e.g. burning, sintering or melting processes
    • C04B2235/66—Specific sintering techniques, e.g. centrifugal sintering
    • C04B2235/667—Sintering using wave energy, e.g. microwave sintering

Definitions

  • the present invention relates to a method for producing crystalline silicon carbide in the form of nanoscale fibers.
  • Silicon carbide is preferred for a variety of applications. For example, it is known to use silicon carbide as an electrode material for batteries such as lithium-ion batteries.
  • the production of crystalline silicon carbide, in particular on a nanocrystalline or microcrystalline scale, is a complex process which requires precise control in order to produce defined silicon carbide, for example in the form of nanocrystalline fibers.
  • the object is achieved according to the invention by a method having the features of claim 1.
  • Preferred embodiments of the invention are disclosed in the subclaims, in the description and in the figure, wherein further described in the subclaims or in the description or the figure or the example or features shown individually or in any combination may constitute an object of the invention unless the context clearly dictates otherwise.
  • the present invention relates to a process for producing crystalline silicon carbide in fiber form, comprising the process steps:
  • silicon carbide can be produced in a particularly defined and reproducible manner, wherein the silicon carbide is obtained in fiber form and in particular as a single crystal in the cubic 3C crystal form.
  • the following process may be carried out completely or individually of process steps a) to c), preferably under protective gas, in particular argon, such that the process proceeds in an atmosphere which is free of oxygen.
  • protective gas in particular argon
  • the above-described method for producing fibrous silicon carbide comprises first according to method step a) providing a mixture with a silicon source, a carbon source and optionally a dopant as starting material, wherein at least the silicon source and the carbon source are present together in particles of a solid granules.
  • each of the particles of the solid granules may thus be preferable for each of the particles of the solid granules to have a carbon source and a silicon source.
  • the silicon source and the carbon source serve to be able to produce silicon carbide in the further process by a reaction of the carbon source with the silicon source. Therefore, the silicon source and the carbon source should be selected such that they can form silicon carbide under the conditions described below, in particular at the following temperatures, such as at normal pressure (lbar) or slight overpressure by the method described above.
  • silicon source or the carbon source is thus not fundamentally limited.
  • Preferred sources of silicon may for example be produced by a sol-gel process, as described below, and about
  • Tetraethyl orthosilicate (TEOS) as a silicon source and sucrose as a carbon source the invention being understood to be not limited to the aforementioned examples.
  • TEOS Tetraethyl orthosilicate
  • the dopant (s) may hereby be added in a basically freely selectable form, for example in a production process of the solid granules, as a soluble compound or may be added elementally, for example metallic. Thus, the dopant may also be part of the solid granules.
  • the dopant as a gas be added to the reactor, wherein the mixture according to process step a) can form directly in the reactor before the temperature treatment.
  • the dopant may be present as a gas.
  • gaseous nitrogen can serve as a dopant.
  • phosphorus (P) or nitrogen (N) may be preferably used for n-type doping, or boron (B) or aluminum (Al) may be used for p-type doping.
  • P phosphorus
  • N nitrogen
  • B boron
  • Al aluminum
  • the silicon carbide produced has a high purity, so that it has semiconductor properties. This is an advantage over commercial fibers (e.g., SCS, Silicon Carbide fibers) which, because of their limited purity, have no semiconductor properties, but may only conduct.
  • the majority charge carriers electrons or holes
  • the energetic properties such as the position of the defect state in the band gap.
  • the method further comprises treating the mixture provided in method step a) with a temperature in a range of> 1650 ° C., for example in a range from> 1650 ° C. to ⁇ 2000 ° C., approximately> 1750 ° C. ⁇ 2000 ° C, especially in a reactor.
  • a temperature in a range of> 1650 ° C., for example in a range from> 1650 ° C. to ⁇ 2000 ° C., approximately> 1750 ° C. ⁇ 2000 ° C, especially in a reactor.
  • silicon carbide it is possible for silicon carbide to form from the carbon source or from the silicon source of the solid granules.
  • a suitable reaction temperature may vary with the doping.
  • the most suitable temperature is adjustable by simply checking the set temperature in the aforementioned range.
  • the starting material passes into the gas phase and form carbon species or silicon species in the gas phase, which react with one another accordingly in a deposition and so as crystalline, in particular Nanoscale fibers can be deposited.
  • Si 2 C and SiC 2 may already be present in the gas phase due to the intimate mixture of silicon and carbon in the solid granules, which leads to an easier formation of SiC on the substrate.
  • a Si-C gas it is possible for a Si-C gas to be present directly, and other gas components, such as SiO 2 or CO 2, may also be present in a manner understandable to a person skilled in the art, the gas components being able to react in particular on the substrate to form silicon carbide.
  • the silicon carbide produced is nanocrystalline in a particularly defined manner in the form of fibers and in detail a cubic 3C structure of the silicon carbide is made possible.
  • the silicon carbide (SiC) is a silicon carbide single crystal, preferably a monocrystalline cubic 3C-SIC, the monocrystalline silicon carbide fibers combine high thermal conductivity, which may be advantageous for certain applications.
  • the concrete form of the silicon carbide produced can be controlled.
  • the temperature in process step b) when setting the temperature in process step b) to a range of about> 1750 ° C to about ⁇ 2000 ° C, about> 1750 ° C to about ⁇ 1850 ° C, at normal pressure (lbar) nanostructured fibers of silicon carbide are formed in a particularly advantageous manner.
  • the substrate or at least one deposition surface thereof is positioned in fluid contact with the educt.
  • the formation of a temperature gradient may be advantageous so that the material of the solid granules or the starting material can pass into the gas phase at a position which has a comparatively higher temperature and can deposit silicon carbide fibers at the comparatively lower temperature, such as, for example a capture surface.
  • a deposition surface may be provided, which has a reduced temperature compared to the abovementioned temperature of the educt in process step b).
  • the temperature of the precipitating surface may be reduced by a temperature ranging from> 50 ° C to ⁇ 100 ° C, compared to the temperature basically set in the reactor or the temperature of the reactant in the aforementioned range of> 1,650 ° C, up to ⁇ 2000 ° C, for example in a range of> 1750 ° C to ⁇ 2000 ° C, such as from> 1750 ° C to ⁇ 1850 ° C.
  • the substrate can be heated to a temperature which is lower than the temperature of the educt by a temperature range of> 50 ° C to ⁇ 100 ° C.
  • one or a plurality of tempering units can be provided for heating the educt and the substrate, as described below.
  • fibers these may in particular be structures in which the ratio of length to diameter is at least greater than or equal to 3: 1, whereas, in contrast to fibers in the case of particles, the ratio of length to diameter is less than 3: 1.
  • the ratio of length to diameter can also be greater than or equal to 10: 1, in particular greater than or equal to 100: 1, for example greater than or equal to 1000: 1.
  • fibers with a diameter in a range of> 10 nm to ⁇ 3 mhi and a length of a few millimeters, for example in a range of> 1 mm to ⁇ 20 mm.
  • fibers differ for example from nanowhiskem (nano-rods) in particular by the bending radius, since rods are only slightly bendable, but fibers very flexible.
  • the substrate or the deposition surface has a seed structure with seed regions, wherein the seed regions are spaced apart by a distance di which is greater than the diameter d F of the fiber material to be produced.
  • this embodiment can lead to fibers can be generated in a defined manner.
  • the Impf Jardinen are spaced apart by a distance di, which is greater than the diameter d F of the fiber material to be produced, it is possible in a particularly defined manner to deposit fibers. Because it can be effectively prevented that the individual precipitating fibers hinder each other in their growth or influence and thus influence the shape of the deposited fibers in no or only poorly controllable way. Thus, it can be particularly preferably made possible by such a seed structure that the fibers can be produced in a very defined manner. It can thus be ensured that the set parameters have a defined effect on the fiber growth and not influenced by the growth of other fibers.
  • the above-described method offers the advantage that it enables the production of qualitatively extremely high-quality silicon carbide in the form of fibers, since very defined conditions can be set.
  • the set parameters are not only adjustable adjustable, but also easily adaptable to the desired field of application, so that further not only high quality but also very adaptable or variable silicon carbide crystals can be generated.
  • the parameters to be set for this include, for example, the selected temperature within the reactor or in the reaction space and the selected temperature of the substrate, including the selected temperature gradient between the reaction space and the substrate.
  • the fibers may possibly be allowed to grow directly on a carbon felt or a carbon foil or another substrate and then be further processed directly in the component, such as the battery. Further separation, purification and / or attachment processes can be dispensed with.
  • the properties of the silicon carbide crystals produced can be set in a simple and defined manner, such as the diameter of crystalline fibers produced, their catches and crystalline quality.
  • the generation of the corresponding heat in process step b) can, for example, be carried out indirectly by resistance heaters made of graphite or molybdenum silicide or more preferably directly by induction, as described in more detail below.
  • the high-temperature treatment according to method step b) takes place with exclusion of oxygen, in particular in an argon atmosphere.
  • these should, as indicated above, be at least 1,650 ° C., approximately at least 1,750 ° C.
  • the chosen temperature is not too high or too low, so that crystalline silicon carbide precipitates as desired and does not precipitate or amorphously deposit or in a high temperature form of S1O2, such as Christobalite.
  • the temperature of the substrate is not below 1750 ° C, with the substrate about 50 ° C to 100 ° C cooler than the starting material.
  • Temperature gradients, heating ramps, hold times and cooling dynamics can be set as parameters. These can further positively influence fiber growth.
  • suitable heating ramps may range from about 500 ° C / min to about 100 ° C / hour, and the silicon carbide formed may be about coolable to room temperature in a range of 15-20 minutes.
  • seed areas provided on the deposition surface which may also be referred to as seed points, the following configurations may be advantageous.
  • the seed structures may comprise, as seed regions, in particular defined topological, morphological or chemical inhomogeneities provided on the deposition surface, wherein only individual ones may contain any combination or all of the aforementioned inhomogeneities of the material of the deposition surface. These inhomogeneities may also form the seed sites of the seed structure.
  • the seed areas may be the areas where fibers grow, such as spots, whereas the seed structures have one or more of the seed areas.
  • a topological inhomogeneity can be understood as meaning, in particular, a surface structuring of the substrate or of the deposition surface.
  • a structuring of the surface of the substrate or of the deposition surface can take place in various sizes in the nano- or macro-range.
  • this may be about a surface roughness or surface porosity.
  • a topological inhomogeneity can be made possible in particular by laser ablation, or focused ion beam etching or chemical etching.
  • specifically defined structures or patterns on the deposition surface can be made possible, such as points, columns, pyramids, lines, screens, carpets or others.
  • the vaccination areas can be particularly defined, which in turn can allow defined fiber growth in particular.
  • morphological inhomogeneity can be understood as meaning, in particular, a structural defect of the substrate or of the material present on the deposition surface.
  • An example may be an offset of the deposition surface or material thereof with silicon carbide.
  • Other examples include multi-phase system locations of a particular phase, phase orientations, or foreign materials.
  • foreign materials are very well suited to favor fiber growth.
  • An example here is the decoration of the surface with metal particles, which function as a growth front at the tip of the fiber, for example in accordance with the vapour-liquid-solid mechanism (VLS).
  • VLS vapour-liquid-solid mechanism
  • examples include, for example, dopants, such as aluminum or other metals or materials that catalytically act on the one-dimensional growth.
  • Condensation of silicon carbide on a particular crystal surface may be energetically favored here, such as salts, metals or ceramic particles.
  • Another possibility would be a decoration of the substrate or of the deposition surface with silicon carbide, for example with silicon carbide particles, for example on a graphite substrate.
  • this can be realized, for example, by polishing a deposition surface made of graphite, for example, with a paste containing silicon carbide particles.
  • silicon carbide particles could also promote fiber growth as seed areas.
  • the seed areas can be particularly defined, which in turn can allow specifically defined fiber growth
  • chemical inhomogeneities in the sense of the present invention, it may be understood in particular that there is a locally limited deposition of atomic monolayers, that is to say in particular a specific compound on the substrate surface or deposition surface.
  • atomic monolayers that is to say in particular a specific compound on the substrate surface or deposition surface.
  • Examples include, for example, graphene deposition on a silicon carbide substrate or localized localization of chemical surface termination on seed sites.
  • Examples include treatment of graphite with nitric acid, which renders the surface reactive and wettable. Such treatment may affect the adsorption of silicon carbide.
  • a difference in surface energy, surface chemistry or surface reactivity can be made possible by chemical inhomogeneities.
  • the inhomogeneities for example, by applying nitric acid or self-assembled monolayers include, for example, dipping, spraying, spin coating, etc. Then, the control of exposure time and / or solution concentration is sufficient to adjust how much surface area has reacted . Another possibility is possibly even with a photoresist (photoresist) cover to allow local exposure. It may further be preferred that the seed regions have a distance in a range from> 20 nm to ⁇ 100 nm, for example from> 50 nm to ⁇ 20 pm, for example from> 50 nm to ⁇ 100 nm, to each other. In particular, in this embodiment, fibers of an advantageous thickness can be produced, which can make a variety of applications possible.
  • the seed areas cover the deposition surface of the substrate in a range of greater than or equal to 5% to less than or equal to 74%, based on the total deposition surface area.
  • the growth of fibers may be particularly preferably made possible because the seed points favor fiber growth, but the number of seed regions is not too high, so that with the limited number of seed regions, the silicon carbide will selectively deposit on the fibers.
  • the above-described values can be dependent on the parameters to be set or the parameters to be selected can be selected when operating the device as a function of the overlap of the deposition surface with seed regions.
  • the educt provided in process step a) is provided using a sol-gel process.
  • a sol-gel process is to be understood in a manner known per se as such a process in which starting materials of the compound to be produced, the so-called precursors, are present in a solvent.
  • the precursor reacts and, by means of polycondensation, first forms particles, for example of a size of ⁇ 10 nm, in the solvent, which is referred to as a sol.
  • a so-called gel is formed which may have, for example, a coalesced network of the particles agglomerated in the sol, with the particles in the intermediate regions Solvent may have stored.
  • a solid can be formed by further treatment, in particular temperature treatment, in particular drying and sintering.
  • This solid can thus be defined by the selection of the precursors, which are the starting materials of the sol-gel process, and contains the carbon source and the silicon source for silicon carbide formation, and may optionally further contain a dopant for doping the silicon carbide already present in the preparation of the sol can be added.
  • the sol-gel process can also be carried out completely or at least partially in a protective atmosphere, in particular in an argon atmosphere.
  • the product of the sol-gel process can in particular be the starting material provided in process step a).
  • the sol-gel process it may preferably be provided that it has at least the following process steps:
  • the educt according to process step a) can be provided in a very defined and reproducible manner in such a way that it reacts in a Thermal treatment or deposition on the substrate silicon carbide in fiber form can form.
  • the precursor solution preparation takes place.
  • the precursor which is the starting material for the sol-gel process
  • a molar ratio of carbon to silicon of 4: 1 at least in a molar excess of carbon generated, so as not to allow only the stoichiometry of the reaction but also to favor the reduction by the carbon excess.
  • a carbohydrate such as sucrose may be used as the carbon source
  • TEOS tetraoxysiloxane
  • the substances may be mixed in a solvent such as ethanol or water.
  • concentrations of the substances used usually do not affect the reaction, but the concentration may have an influence on the following step, the formation of a sol.
  • a highly concentrated solution is thicker and gelled faster and therefore is well suited to produce a granulate as starting material according to process step a), which may be advantageous for fiber production of silicon carbide.
  • the solution is less concentrated and thus less viscous, it can be used, for example, for single or multiple infiltration of porous structures or for coating substrates.
  • the latter may be suitable for an alternately doped multilayer structure, which may be advantageous for example for charge transfer processes in electronic or catalytic applications.
  • silicon carbide fibers can be produced.
  • the fibers may be so multi-layered, such as with an inner, N-doped layer and an outer, Al-doped layer, or grow as segmented fibers.
  • the one deposition surface may be part of a porous substrate, that is to say for some to be internal Is present surface of the substrate, or that a Abscheidenober Structure is part of a closed substrate, that is present as the outer surface of the substrate.
  • the Abscheidenober configuration thus be particularly flat.
  • the substrate is at least partially porous, wherein the fiber formation takes place at least partially within the pores of the substrate and / or that the substrate is at least partially closed, ie has an at least partially closed Abscheideober Design.
  • the catalyst used may in particular be an acid present in the solvent, for example hydrochloric acid.
  • the amount of catalyst relative to the silicon precursor affects the gelation rate, that is, molecular formation of silicate networks rather than particle growth. These differences can also affect the silicon carbide end product.
  • a molar ratio of TEOS to water to sucrose to hydrochloric acid may be 1 to 6.5 to 0.3 to 0.06 in order to produce fibers of silicon carbide particularly advantageously in the further process.
  • a dopant can be added even during the sol formation.
  • any doping substances or dopants which are at least partially soluble or dispersible in the corresponding solvent, such as, for example, ethanol of the water, are suitable.
  • the dopant should not be volatile, evaporate or sublime or otherwise decompose, since otherwise the further reaction steps would not be feasible.
  • dopants include, for example, those mentioned above.
  • aluminum such as a powder
  • the catalyst such as hydrochloric acid
  • AlCb is formed.
  • these may not be completely dissolved but are protected by an AlCh coating around an aluminum core so that they remain intact until the subsequent high-temperature treatment, ie process step b), corresponding particles being referred to as growth front according to US Pat vapor-liquid-solid theory could prefer the fiber growth in process step c).
  • the gelation may be after the preparation of the sol in particular two steps, namely first a treatment at about 60 ° C, for example in a closed container, and then at about> 60 ° C to ⁇ l20 ° C.
  • the sol produced as described above can be used for the purpose of infiltrating, coating or producing bulk material, for example for producing silicon carbide fibers on a flat or closed substrate.
  • relatively thick solutions or sols can be gelled directly in the reaction vessel for the preparation of precursor granules.
  • smooth, structured or nano- or microporous or macroporous substrates can be infiltrated from carbon, for example.
  • the precursor deposited thereon would have the possibility of reacting in a very efficient and defined manner in the further steps and of generating the reaction gases necessary for silicon carbide growth.
  • fiber growth in such infiltrated structures can be carried out in a preferred and efficient manner.
  • the substrate may be positioned at the junction to a cooler zone, or the fibers may grow due to local fluctuations or cooling of the reactor, such as the crucible.
  • a porous structure could be pre-decorated with metal particles prior to treatment with the precursor sol to subsequently control fiber formation. This can be done, for example, according to the vapour-solid mechanism with metal drops as a growth front.
  • the previously generated sol in the porous structure or in a particular closed vessel of an elevated temperature set off.
  • Two processes should take place, namely, network formation of the silicate and reduction of the carbon compound, such as the cleavage and reduction of the sucrose by the catalyst, such as hydrochloric acid, and heat. Network formation may occur at about 60 ° C for more than 12 hours, whereas another step may occur at 60-120 ° C for 4 hours or more. Since the chosen conditions can affect the final product, a multi-step reaction may be beneficial.
  • treatment at elevated temperature may first be carried out in a range from> 40 ° C to ⁇ 90 ° C and the second step at temperatures> 60 ° C to ⁇ 120 ° C, at> 90 ° C to ⁇ 120 ° C.
  • the gelation can take place in a closed container.
  • a further step may follow, a drying of the gel.
  • the vessel can be opened and the solvent can evaporate by means of a temperature treatment at or above the boiling point.
  • the formation of dense structures on the one side or pores, cracks or disintegration into granules of various sizes may occur because the gel structure condenses due to capillary forces of the outflowing solvent.
  • the decomposition of the carbohydrate proceeds.
  • the chosen conditions can be decisive for the properties of the fiber material to be produced from silicon carbide. For example, drying for 24 hours at temperatures of> 100 ° C to ⁇ 160 ° C. The duration and the temperatures may be dependent on the solvent used or its boiling point, and the temperature and the duration of the aforementioned step.
  • the gel produced as described above can then be sintered according to method step f) at a temperature in a range of> 800 ° C to ⁇ 1200 ° C, in particular in a range of> 900 ° C to ⁇ 10000 ° C. It may be of importance that in the method described here, the sintering of the precursor gel takes place in contrast to conventional sol-gel preparations of silicates with exclusion of oxygen. The silicate is vitrified and the carbohydrate finally pyrolized. Relevant details for the precursor structure and thus for the final end product can be in particular the following. First of all, the work may be in the absence of oxygen and, in particular, in a protective gas atmosphere, such as argon atmosphere, for instance under an argon stream or static.
  • a protective gas atmosphere such as argon atmosphere
  • temperature control may be important, such as heating rates, temperature and duration of the temperature treatment.
  • the sintered precursor microstructure may be relevant to the properties of the final silicon carbide product since in the next step, the carbothermal reduction of process step a), as described above, may affect the composition and dynamics of release of the reaction gases. Furthermore, the type of doping may be of importance as far as desired. In the following step, the dopant used, for example, in sol formation is of importance, since it must be stable, as indicated above, even at high temperatures. Another possibility would be core / shell particles in which the selected dopant is present as a core, wherein the core is covered by a high-temperature-stable substance, which acts as a protective shell for the core.
  • step a) By way of example, mention may be made of the compound described above, in which elemental aluminum is originally coated with Al 2 O 3 or by reaction with the catalyst, such as hydrochloric acid, with AlCb.
  • the catalyst such as hydrochloric acid
  • step b) a carbothermal reduction.
  • carbon in the solid granules provided in accordance with method step a), carbon is present in a greater than equimolar amount with respect to silicon.
  • the carbon content can be chosen such that in a reaction of all silicon to silicon carbide even more carbon is present.
  • carbon with respect to silicon may be present in an amount of> 1/1 to ⁇ 5/1, based on the molar proportions.
  • the process can be particularly simple, since by the so taking place modification of the surface of Siliziumcarbidfasem or silicon carbide particles by forming a carbon layer or carbon layer on the surface of an oxidation of silicon or a formation of silicon oxide particularly effective even when stored in air can be effectively prevented over a longer period.
  • it can be effectively prevented that additional steps for removing a silicon oxide layer become necessary in order to enable an effective insertion of lithium compounds when operating as an electrode in a lithium-ion battery or in a lithium-ion battery. It can thus be generated by a relatively simple and straightforward change in stoichiometry during the sol-gel process, a protective layer with the desired antioxidant properties. In this case, no additional step is necessary, which makes the method particularly cost-effective and time-saving feasible.
  • the method is carried out in a device comprising:
  • a receptacle for receiving an at least partially electrically conductive starting material
  • an induction coil for generating an alternating magnetic field, wherein the induction coil is arranged such that at least the educt by a through the magnetic alternating field induced current can be heated to a defined temperature, which is in a range of> 1650 ° C, preferably up to ⁇ 2000 ° C; and
  • the substrate is positioned in fluid contact with the educt and wherein the substrate is heatable to a temperature lower than the temperature of the educt by a temperature range of> 50 ° C to ⁇ 100 ° C, and wherein the substrate has a seed structure with Vaccination regions, wherein the seed portions are spaced from each other by a distance di, which is greater than the diameter d F of the fibers to be produced.
  • such a device is suitable for being able to set the desired process parameters in a defined manner.
  • the receptacle serves to receive and in particular enclose an at least partially electrically conductive educt, as described in detail above.
  • the product may be electrically conductive from a sol-gel process as described above. In order to position the educt in the receptacle this may have a material lock or be closed about by a lid.
  • the receptacle can be designed as a particularly electrically conductive, formed from graphite, crucible.
  • an induction coil for generating electromagnetic radiation is furthermore provided as the heating device.
  • the coil is arranged such that at least the starting substance or the starting material can be heated to a defined temperature by one of an alternating electromagnetic field generated by the coil, which ranges from> 1650 ° C., to ⁇ 2000 ° C, for example in a range from> 1750 ° C to ⁇ 2000 ° C, such as from> 1750 ° C to ⁇ 1850 ° C.
  • This allows the starting material to be in suitable species in the gas phase pass over, whereby deposited from these species silicon carbide as nanoscale monocrystalline fibers.
  • the device further comprises a substrate for depositing fiber material produced from the educt.
  • the substrate has a deposition surface or a plurality of deposition surfaces.
  • the substrate or at least the deposition surface is formed from graphite.
  • a suitable positioning of the substrate should be ensured within the coil, so that the substrate is heated in not too strong.
  • the substrate may be made of vitreous carbon, monocrystalline silicon carbide, polycrystalline silicon carbide, another high temperature stable and reduction resistant ceramic, or a high temperature stable metal such as tungsten, tantalum or molybdenum.
  • the temperature in the reactor and the temperature of the substrate or the deposition surface are different from each other.
  • a sufficiently high temperature may be present within the receiving space in order to bring the corresponding substances or the educt (s) into the gas phase or to keep them in the gas phase.
  • the interior of the receptacle serves as a reaction space having a volume in which the starting materials of Siliziumcarbidher ein go into the gas phase or remain in the gas phase.
  • the substrate may also be advantageous for the substrate to have a temperature which is reduced compared to the temperature in the reaction space, as described above.
  • the position of at least one of the receptacle and the substrate relative to the induction coil is variable by means of a displacement device.
  • a particularly advantageous and adaptable temperature control can be made possible, which can make the formation of fibers particularly defined.
  • the positioning of the receiving device with the starting substance or of the substrate can in particular be configured in such a way that the starting substance is arranged in the comparatively hotter zone and the substrate or its deposition surface can be positioned in a comparatively colder region, since the mass transport differs from the comparative one warmer zone takes place to the relatively colder zone and so the fiber growth can be made possible.
  • the aforementioned method may be suitable, for example, to produce silicon carbide fibers as electrode material for a battery, such as, in particular, a lithium-ion battery.
  • a battery such as, in particular, a lithium-ion battery.
  • the thermal management of the battery can be improved by the good thermal properties of the fiber material.
  • the chemical and thermal durability of the fibers may be advantageous for fishing time stability, and the flexibility of the silicon carbide, especially as fibers, may be advantageous for high cycle stability.
  • polycrystalline forms of the silicon carbide are also conceivable within the scope of the present invention. It is also advantageous that silicon carbide can have a high capacitance as an electrode material, so that an electrode material produced as described can further enable a good power capability of a battery.
  • silicon carbide thus produced include, for example, areas of photonics, such as solar cells, for example, which can act accordingly differently doped Siliziumcarbidfasem, LEDs in which, for example, organic light surfaces can be provided in luminous textiles based on silicon carbide, or the structural reinforcement, such as other lasers.
  • the method is very effective, since in an exemplary device or by a method described above very large amounts of Siliciumcarbidfasem can be generated.
  • FIG. 1 is a schematic sectional view through a device according to the invention
  • FIG. 2 is a schematic plan view of a deposition surface of a substrate.
  • FIG. 1 shows an apparatus 10 for producing silicon carbide as fibers.
  • the device comprises a receptacle 12 for receiving an at least partially electrically conductive starting material, which can be arranged at the bottom of the receptacle 12.
  • the receptacle 12 is designed as a particular made of graphite and thus electrically conductive ausgestalteter crucible comprising a crucible pan 16 and a crucible lid 18. By arranging the crucible lid 18 on the crucible pan 16 of the crucible or the receptacle 12 is closed gas-tight.
  • the crucible lid 18 serves as a substrate 20 for depositing fibers. As a result, it can be easily made possible for the substrate 20 to be positioned in fluid contact with the educt. Furthermore, the substrate 20 is described with reference to FIG.
  • FIG. 2 shows that the substrate 20 has a seed structure 22 with seed regions 24, wherein the seed regions 24 are spaced apart by a distance d 1 which is greater than the diameter of the fiber material to be produced.
  • the distance di may be in a range from> 20 nm to ⁇ 1 OOmhi, for example from> 50 nm to ⁇ 20mhi, for example from> 50 nm to ⁇ 100 nm.
  • the seed regions 24 may be formed at least in part by topological inhomogeneities, at least in part by morphological inhomogeneities and / or at least in part by chemical inhomogeneities. There may be one or a selectable combination of the aforementioned inhomogeneities. In principle, it may be advantageous if the substrate 20 has been germinated with aluminum or silicon carbide.
  • the device 10 is shown to include an induction coil 26 for generating electromagnetic radiation.
  • the induction coil 26 is arranged such that at least the educt by the electromagnetic radiation to a defined temperature is heatable, which is in a range of> 1650 ° C, for example> 1750 ° C, about to ⁇ 2000 ° C.
  • the substrate 20 can be heated to a temperature which is lower than the temperature of the educt over a temperature range of> 50 ° C to ⁇ 100 ° C. This can be achieved by a suitable positioning of educt and substrate 20, that is, for example, of the crucible or of the receiving container 12 within the induction coil 26.
  • a pull rod 30 is provided, which is hinged to the receptacle 12 and a crucible holder 32 and thus this in particular in the axial direction in the induction coil 26 is movable.
  • the induction coil 26 and the receptacle 12 are arranged in a housing 34.
  • the housing 34 can thus form a heating chamber.
  • the housing 34 has a first viewing window 36 for a temperature measurement, for example for using a thermal camera, and also has a further viewing window 38.
  • two gas ports 38 are provided, through which protective gas, such as argon can be introduced and also a gas port 40 for connecting a vacuum pump.
  • the receptacle 12 can be removed from the housing 34 or accessible in the housing 34 in order to equip it with educt and / or to remove the fibers.
  • Temperature control to produce fibers of silicon carbide For example, a graphite crucible as a receptacle 12 in an induction coil 26 lOOmm in length and 60mm diameter at a certain time a temperature of 1850 ° C in the center but only l750 ° C in the end, or generate in the axial or radial outer area, since the magnetic field in regions outside the induction coil 26 is weaker.
  • a method for producing fiber material made of silicon carbide can thus be carried out.
  • Such a method can have the following method steps in the broadest application:
  • silicon carbide in particular a composite or a compound which contains suitable proportions of carbon and silicon, for example in a ratio of 4: 1, may be suitable.
  • These may be, for example, organometallic precursors, silicates, elemental silicon, and / or carbohydrates or polymers.
  • the reducing effect of the carbon begins, on the one hand directly via elemental carbon, indirectly via carbon monoxide (CO) in the resulting gas as a carbothermal reduction .
  • the carbon can reduce the C / Si precursor or the educt, especially S1O2 contained, in contact or via the gas phase to SiO gas and subsequently to silicon carbide on the substrate 20.
  • the educt or the carbonaceous and silicon-containing precursor is thereby inserted, for example, in the graphite crucible and in the middle of the Induction coil 26 is positioned, which can be conveniently connected to a high frequency generator.
  • the alternating magnetic field generated in the induction coil 26 induces a current in the at least partially electrically conductive starting material and optionally in a conductive wall of the receiving container 12.
  • the educt is heated by the electrical resistance in a very defined manner.
  • the receptacle 12 is also electrically conductive, it can thus also be heated. If it is electrically insulating, which is basically possible, such as made of aluminum oxide (Al 2 O 3 ), only the starting material can be heated, both variants can have application-related advantages.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Organic Chemistry (AREA)
  • Materials Engineering (AREA)
  • Inorganic Chemistry (AREA)
  • Manufacturing & Machinery (AREA)
  • Ceramic Engineering (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • Metallurgy (AREA)
  • Structural Engineering (AREA)
  • Dispersion Chemistry (AREA)
  • Nanotechnology (AREA)
  • Physics & Mathematics (AREA)
  • Geometry (AREA)
  • Carbon And Carbon Compounds (AREA)
  • Crystals, And After-Treatments Of Crystals (AREA)

Abstract

La présente invention concerne un procédé de fabrication de carbure de silicium cristallin sous forme de fibres, ce procédé comprenant les étapes suivantes : a) préparation d'un mélange comprenant une source de silicium, une source de carbone et éventuellement un dopant, au moins la source de silicium et la source de carbone étant présentes conjointement dans des particules d'un granulat solide, comme produit de départ ; b) traitement du produit de départ préparé à l'étape a) à une température située dans une plage ≥ 1650 °C ; c) dépôt de fibres ayant un diamètre d F en carbure de silicium sur un substrat, le substrat (20) étant placé en contact fluidique avec le produit de départ et le substrat (20) pouvant être chauffé à une température qui est inférieure à la température du produit de départ d'une valeur située dans la plage de températures ≥ 50 °C et ≤ 100 °C, et le substrat (20) présentant une structure de germination (22) comprenant des zones de germination (24), ces zones de germination (24) étant espacées les unes des autres par une distance d qui est supérieure au diamètre d F des fibres à produire.
PCT/EP2019/050413 2018-01-12 2019-01-09 Procédé de fabrication de carbure de silicium WO2019137944A1 (fr)

Priority Applications (1)

Application Number Priority Date Filing Date Title
EP19700866.7A EP3737646A1 (fr) 2018-01-12 2019-01-09 Procédé de fabrication de carbure de silicium

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE102018100681.0A DE102018100681A1 (de) 2018-01-12 2018-01-12 Verfahren zum Herstellen von Siliziumcarbid
DE102018100681.0 2018-01-12

Publications (1)

Publication Number Publication Date
WO2019137944A1 true WO2019137944A1 (fr) 2019-07-18

Family

ID=65036760

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/EP2019/050413 WO2019137944A1 (fr) 2018-01-12 2019-01-09 Procédé de fabrication de carbure de silicium

Country Status (3)

Country Link
EP (1) EP3737646A1 (fr)
DE (1) DE102018100681A1 (fr)
WO (1) WO2019137944A1 (fr)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN114735703A (zh) * 2022-04-28 2022-07-12 中电化合物半导体有限公司 一种碳化硅纤维的合成方法及应用

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
RU2758311C9 (ru) * 2021-03-24 2021-12-08 Федеральное государственное бюджетное учреждение науки Институт металлургии и материаловедения им. А.А. Байкова Российской академии наук (ИМЕТ РАН) Способ получения карбидкремниевого войлока

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3721732A (en) * 1966-12-14 1973-03-20 Philips Corp Method of manufacturing filamentary bodies of circular cross-section consisting of silicon carbide single crystals and filamentary bodies obtained by said method
WO2016078955A1 (fr) * 2014-11-18 2016-05-26 Universität Paderborn Procédé pour la fabrication d'un matériau d'électrode pour une électrode de batterie
DE102015104943A1 (de) * 2015-03-31 2016-10-06 Universität Paderborn Verfahren zum Herstellen eines nano- oder mikrostrukturierten Schaumstoffs

Family Cites Families (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5037626A (en) * 1988-11-22 1991-08-06 Union Oil Company Of California Process for producing silicon carbide whiskers using seeding agent
US5455212A (en) * 1994-03-15 1995-10-03 The University Of British Columbia In situ production of silicon carbide-containing ceramic composite powders
US6221154B1 (en) * 1999-02-18 2001-04-24 City University Of Hong Kong Method for growing beta-silicon carbide nanorods, and preparation of patterned field-emitters by chemical vapor depositon (CVD)
JP3918073B2 (ja) * 2001-06-25 2007-05-23 独立行政法人科学技術振興機構 ３Ｃ−ＳｉＣナノウィスカーの合成方法及び３Ｃ−ＳｉＣナノウィスカー
DE102006055469A1 (de) * 2006-11-23 2008-05-29 Universität Paderborn Verfahren zur Herstellung eines Gegenstandes zumindest teilweise mit Siliziumkarbidgefüge aus einem Rohling aus einem kohlenstoffhaltigen Material
FR2924362B1 (fr) * 2007-11-30 2012-07-13 Centre Nat Rech Scient Reacteur chimique avec superstructure nanometrique

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3721732A (en) * 1966-12-14 1973-03-20 Philips Corp Method of manufacturing filamentary bodies of circular cross-section consisting of silicon carbide single crystals and filamentary bodies obtained by said method
WO2016078955A1 (fr) * 2014-11-18 2016-05-26 Universität Paderborn Procédé pour la fabrication d'un matériau d'électrode pour une électrode de batterie
DE102015104943A1 (de) * 2015-03-31 2016-10-06 Universität Paderborn Verfahren zum Herstellen eines nano- oder mikrostrukturierten Schaumstoffs

Non-Patent Citations (6)

* Cited by examiner, † Cited by third party
Title
BETTINA FRIEDEL ET AL: "Wide Bandgap Semiconductors - Nanowires of p- and n-type Silicon Carbide", MRS PROCEEDINGS, vol. 963, 1 January 2006 (2006-01-01), pages 0963-Q15-10, XP055241780, DOI: 10.1557/PROC-0963-Q15-10 *
BETTINA FRIEDEL: "3C-Siliziumkarbid auf Sol-Gel-Basis : Entwicklung, Wachstumsmechanismen und Charakter anwendungsorientierter Morphologien des Wide-Bandgap-Halbleiters", 1 August 2007 (2007-08-01), Paderborn, pages 1 - 158, XP055571657, Retrieved from the Internet <URL:https://epo.summon.serialssolutions.com/2.0.0/link/0/eLvHCXMwlV07b8JADLZALO3UqpX6lG7o2KPkxSXt1gjC0C6AxBjdJZfqRAiIECH1h_T31g5JxdCFIVOci-LTObY_-zPAk1Q0viFxuCeHGKA4ict9ZQfcVcNBkKjASnSd0w3deSSmkfvRgbe2F6bZXyqPTAg9JSyfKpQO80ccDAdeplHf7mNoF3iCoEmvCz0qhBQNZvmvDFradsmj38f4As6PsmOX0NHFFfw4IZ-Z3HybarWUW2VSJqu> [retrieved on 20190320], DOI: 10.13140/RG.2.1.2957.1445 *
BOOTSMA ET AL: "Growth of SiC whiskers in the system SiO2-C-H2 nucleated by iron", JOURNAL OF CRYSTAL GROWTH, ELSEVIER, AMSTERDAM, NL, vol. 11, no. 3, 1 December 1971 (1971-12-01), pages 297 - 309, XP022161642, ISSN: 0022-0248, DOI: 10.1016/0022-0248(71)90100-X *
H. -P. MARTIN ET AL: "Silicon carbide derived from silica sol and sugar", JOURNAL OF MATERIALS SCIENCE LETTERS., vol. 14, no. 9, 1 January 1995 (1995-01-01), GB, pages 620 - 622, XP055572542, ISSN: 0261-8028, DOI: 10.1007/BF00586158 *
Q.-S. CHEN ET AL.: "Effects of induction heating on temperature distribution and growth rate in large-size SiC growth system", JOURNAL OF CRYSTAL GROWTH, vol. 266, no. 1-3, pages 320 - 326, XP004505912, DOI: doi:10.1016/j.jcrysgro.2004.02.061
Y.J. WU ET AL., SYNTHESIS OF SS-SIC NANOWHISKERS BY HIGH TEMPERATURE EVAPORATION OF SOLID REACTANTS

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN114735703A (zh) * 2022-04-28 2022-07-12 中电化合物半导体有限公司 一种碳化硅纤维的合成方法及应用

Also Published As

Publication number Publication date
EP3737646A1 (fr) 2020-11-18
DE102018100681A1 (de) 2019-07-18

Similar Documents

Publication Publication Date Title
DE3856514T2 (de) Sublimationsanwachsen von Siliziumkarbideinkristallen
EP3230205B1 (fr) Procédé pour la fabrication d&#39;un matériau d&#39;électrode pour une électrode de batterie
EP3245158B1 (fr) Dispositif et procédé de fabrication de carbure de silicium
DE69802898T2 (de) Verfahren zur herstellung von kohlenstoffnanoröhren, verfahren zur herstellung von kohlenstoffnanoröhrenfilm und struktur versehen mit kohlenstoffnanoröhrenfilm
EP3277645B1 (fr) Procédé de fabrication d&#39;un corps contenant du carbure de silicium
Lupan et al. Synthesis of one-dimensional SnO2 nanorods via a hydrothermal technique
Ling et al. One-dimensional single-crystalline bismuth oxide micro/nanoribbons: morphology-controlled synthesis and luminescent properties
AT14701U1 (de) Beschichtungsquelle zur Herstellung dotierter Kohlenstoffschichten
EP3737646A1 (fr) Procédé de fabrication de carbure de silicium
DE60125472T3 (de) SiC Material und Verfahren zu seiner Herstellung
EP3277646A1 (fr) Procédé de fabrication d&#39;une mousse nanostructurée ou microstructurée
EP3268512B1 (fr) Procédé pour la production d&#39;une électrode, électrode et dispositif d&#39;électrolyse
Wang et al. Large-scale synthesis of aligned hexagonal ZnO nanorods using chemical vapor deposition
KR101067408B1 (ko) 수밀도의 조정이 가능한 초장 산화아연 나노 와이어 다발의제조 방법
CN113668053A (zh) 黑磷薄膜反应装置、黑磷薄膜制备方法
EP1341737B1 (fr) Utiilisation d&#39;un substrat a base de nitrure de silicium pour fabriquer des composants semi-conducteurs
Gerges et al. AlN hollow-nanofilaments by electrospinning
DE102017114243A1 (de) Verfahren zur Herstellung von siliciumcarbidhaltigen Fasern und Schäumen sowie ihre Verwendung
WO2019137942A1 (fr) Dispositif et procédé de fabrication de carbure de silicium
CN113104885B (zh) 非层状Sn2P2S6纳米片的制备方法及其在光催化析氢领域的应用
DE112020005871T5 (de) Verfahren zur Herstellung von Materialien auf Basis von BSCCO
US20230037291A1 (en) Sol-gel synthesis of max phase functional materials
DE102018132244B4 (de) Verfahren zur Herstellung von dotierten Halbleiterschichten
EP4419729A1 (fr) Appareil et procédé de production de couches de diamant dopé
EP3265424B1 (fr) Procédé pour fabriquer un matériau composite transparent renforcé par des fibres et matériau composite transparent renforcé par des fibres

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 19700866

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

ENP Entry into the national phase

Ref document number: 2019700866

Country of ref document: EP

Effective date: 20200812