C
CHEMISTRY; METALLURGY

Note(s)

  • In section C, the definitions of groups of chemical elements are as follows:
    • Alkali metals: Li, Na, K, Rb, Cs, Fr
    • Alkaline earth metals: Ca, Sr, Ba, Ra
    • Lanthanides: elements with atomic numbers 57 to 71 inclusive
    • Rare earths: Sc, Y, Lanthanides
    • Actinides: elements with atomic numbers 89 to 103 inclusive
    • Refractory metals: Ti, V, Cr, Zr, Nb, Mo, Hf, Ta, W
    • Halogens: F, Cl, Br, I, At
    • Noble gases: He, Ne, Ar, Kr, Xe, Rn
    • Platinum group: Os, Ir, Pt, Ru, Rh, Pd
    • Noble metals: Ag, Au, Platinum group
    • Light metals: alkali metals, alkaline earth metals, Be, Al, Mg
    • Heavy metals: metals other than light metals
    • Iron group: Fe, Co, Ni
    • Non-metals: H, B, C, Si, N, P, O, S, Se, Te, noble gases, halogens
    • Metals: elements other than non-metals
    • Transition elements: elements with atomic numbers 21 to 30 inclusive, 39 to 48 inclusive, 57 to 80 inclusive, 89 upwards
  • Section C covers :
    • pure chemistry, which covers inorganic compounds, organic compounds, macromolecular compounds, and their methods of preparation;
    • applied chemistry, which covers compositions containing the above compounds, such as: glass, ceramics, fertilisers, plastics compositions, paints, products of the petroleum industry. It also covers certain compositions on account of their having particular properties rendering them suitable for certain purposes, as in the case of explosives, dyestuffs, adhesives, lubricants, and detergents;
    • certain marginal industries, such as the manufacture of coke and of solid or gaseous fuels, the production and refining of oils, fats and waxes, the fermentation industry (e.g., brewing and wine-making), the sugar industry;
    • certain operations or treatments, which are either purely mechanical, e.g., the mechanical treatment of leather and skins, or partly mechanical, e.g., the treatment of water or the prevention of corrosion in general;
    • metallurgy, ferrous or non-ferrous alloys.
  • In all sections of the IPC, in the absence of an indication to the contrary, the Periodic System of chemical elements referred to is the one with 8 groups as represented in the table below. For example, group C07F 3/00"Compounds containing elements of the 2nd Group of the Periodic System" refers to the elements of columns IIa and IIb.
    • fig401
    • In the case of operations, treatments, products or articles having both a chemical and a non-chemical part or aspect, the general rule is that the chemical part or aspect is covered by section C.
    • In some of these cases, the chemical part or aspect brings with it a non-chemical one, even though purely mechanical, because this latter aspect either is essential to the operation or treatment or constitutes an important element thereof. It has seemed, in fact, more logical not to dissociate the different parts or aspects of a coherent whole. This is the case for applied chemistry and for the industries, operations and treatments mentioned in Notes (1)(c), (d) and (e). For example, furnaces peculiar to the manufacture of glass are covered by class C03 and not by class F27.
    • There are, however, some exceptions in which the mechanical (or non-chemical) aspect carries with it the chemical aspect, for example:
      • Certain extractive processes, in subclass A61K;
      • The chemical purification of air, in subclass A61L;
      • Chemical methods of fire-fighting, in subclass A62D;
      • Chemical processes and apparatus, in class B01;
      • Impregnation of wood, in subclass B27K;
      • Chemical methods of analysis or testing, in subclass G01N;
      • Photographic materials and processes, in class G03, and, generally, the chemical treatment of textiles and the production of cellulose or paper, in section D.
    • In still other cases, the pure chemical aspect is covered by section C and the applied chemical aspect by another section, such as A, B or F, e.g., the use of a substance or composition for:
      • treatment of plants or animals, covered by subclass A01N;
      • foodstuffs, covered by class A23;
      • ammunition or explosives, covered by class F42.
    • When the chemical and mechanical aspects are so closely interlocked that a neat and simple division is not possible, or when certain mechanical processes follow as a natural or logical continuation of a chemical treatment, section C may cover, in addition to the chemical aspect, a part only of the mechanical aspect, e.g., after-treatment of artificial stone, covered by class C04. In this latter case, a note or a reference is usually given to make the position clear, even if sometimes the division is rather arbitrary.
METALLURGY
C30
CRYSTAL GROWTH (separation by crystallisation in general B01D 9/00) [3]
C30B
SINGLE-CRYSTAL GROWTH (by using ultra-high pressure, e.g. for the formation of diamonds B01J 3/06); UNIDIRECTIONAL SOLIDIFICATION OF EUTECTIC MATERIAL OR UNIDIRECTIONAL DEMIXING OF EUTECTOID MATERIAL; REFINING BY ZONE-MELTING OF MATERIAL (zone-refining of metals or alloys C22B); PRODUCTION OF A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE (casting of metals, casting of other substances by the same processes or devices B22D; working of plastics B29; modifying the physical structure of metals or alloys C21D, C22F); SINGLE CRYSTALS OR HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; AFTER-TREATMENT OF SINGLE CRYSTALS OR A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE (for producing semiconductor devices or parts thereof H01L); APPARATUS THEREFOR [3]

Note(s)

  • In this subclass, the following expressions are used with the meaning indicated:
    • "single crystal" includes also twin crystals and a predominantly single crystal product;
    • "homogeneous polycrystalline material" means a material with crystal particles, all of which have the same chemical composition;
    • "defined structure" means the structure of a material with grains which are oriented in a preferential way or have larger dimensions than normally obtained.
  • In this subclass:
    • the preparation of single crystals or a homogeneous polycrystalline material with defined structure of particular materials or shapes is classified in the group for the process as well as in group C30B 29/00;
    • an apparatus specially adapted for a specific process is classified in the appropriate group for the process. Apparatus to be used in more than one kind of process is classified in group C30B 35/00.
Subclass index
SINGLE-CRYSTAL GROWTH
from solids or gels 1/00, 3/00, 5/00
from liquids 7/00-21/00, 27/00
from vapours 23/00, 25/00
PRODUCTION OF SINGLE CRYSTALS OR HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE 28/00, 30/00
SINGLE CRYSTALS OR HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE 29/00
AFTER-TREATMENT 31/00, 33/00
APPARATUS 35/00
Single-crystal growth from solids or gels [3]
C30B 1/00
Single-crystal growth directly from the solid state (unidirectional demixing of eutectoid materials C30B 3/00; under a protective fluid C30B 27/00) [3]
C30B 1/02
by thermal treatment, e.g. strain annealing (C30B 1/12 takes precedence) [3]
C30B 1/04
Isothermal recrystallisation [3]
C30B 1/06
Recrystallisation under a temperature gradient [3]
C30B 1/08
Zone recrystallisation [3]
C30B 1/10
by solid state reactions or multi-phase diffusion [3]
C30B 1/12
by pressure treatment during the growth [3]
C30B 3/00
Unidirectional demixing of eutectoid materials [3]
C30B 5/00
Single-crystal growth from gels (under a protective fluid C30B 27/00) [3]
C30B 5/02
with addition of doping materials [3]
Single-crystal growth from liquids; Unidirectional solidification of eutectic materials [3]
C30B 7/00
Single-crystal growth from solutions using solvents which are liquid at normal temperature, e.g. aqueous solutions (from molten solvents C30B 9/00; by normal or gradient freezing C30B 11/00; under a protective fluid C30B 27/00) [3]
C30B 7/02
by evaporation of the solvent [3]
C30B 7/04
using aqueous solvents [3]
C30B 7/06
using non-aqueous solvents [3]
C30B 7/08
by cooling of the solution [3]
C30B 7/10
by application of pressure, e.g. hydrothermal processes [3]
C30B 7/12
by electrolysis [3]
C30B 7/14
the crystallising materials being formed by chemical reactions in the solution [3]
C30B 9/00
Single-crystal growth from melt solutions using molten solvents (by normal or gradient freezing C30B 11/00; by zone-melting C30B 13/00; by crystal pulling C30B 15/00; on immersed seed crystal C30B 17/00; by liquid phase epitaxial growth C30B 19/00; under a protective fluid C30B 27/00) [3]
C30B 9/02
by evaporation of the molten solvent [3]
C30B 9/04
by cooling of the solution [3]
C30B 9/06
using as solvent a component of the crystal composition [3]
C30B 9/08
using other solvents [3]
C30B 9/10
Metal solvents [3]
C30B 9/12
Salt solvents, e.g. flux growth [3]
C30B 9/14
by electrolysis [3]
C30B 11/00
Single-crystal-growth by normal freezing or freezing under temperature gradient, e.g. Bridgman- Stockbarger method (C30B 13/00, C30B 15/00, C30B 17/00, C30B 19/00 take precedence; under a protective fluid C30B 27/00) [3]
C30B 11/02
without using solvents (C30B 11/06 takes precedence) [3]
C30B 11/04
adding crystallising materials or reactants forming it in situ to the melt [3]
C30B 11/06
at least one but not all components of the crystal composition being added [3]
C30B 11/08
every component of the crystal composition being added during the crystallisation [3]
C30B 11/10
Solid or liquid components, e.g. Verneuil method [3]
C30B 11/12
Vaporous components, e.g. vapour-liquid-solid-growth [3]
C30B 11/14
characterised by the seed, e.g. its crystallographic orientation [3]
C30B 13/00
Single-crystal growth by zone-melting; Refining by zone-melting (C30B 17/00 takes precedence; by changing the cross-section of the treated solid C30B 15/00; under a protective fluid C30B 27/00; for the growth of homogeneous polycrystalline material with defined structure C30B 28/00; zone-refining of specific materials, see the relevant subclasses for the materials) [5]
C30B 13/02
Zone-melting with a solvent, e.g. travelling solvent process [3]
C30B 13/04
Homogenisation by zone-levelling [3]
C30B 13/06
the molten zone not extending over the whole cross-section [3]
C30B 13/08
adding crystallising materials or reactants forming it in situ to the molten zone [3]
C30B 13/10
with addition of doping materials [3]
C30B 13/12
in the gaseous or vapour state [3]
C30B 13/14
Crucibles or vessels [3]
C30B 13/16
Heating of the molten zone [3]
C30B 13/18
the heating element being in contact with, or immersed in, the molten zone [3]
C30B 13/20
by induction, e.g. hot wire technique (C30B 13/18 takes precedence) [3]
C30B 13/22
by irradiation or electric discharge [3]
C30B 13/24
using electromagnetic waves [3]
C30B 13/26
Stirring of the molten zone [3]
C30B 13/28
Controlling or regulating [3]
C30B 13/30
Stabilisation or shape controlling of the molten zone, e.g. by concentrators, by electromagnetic fields; Controlling the section of the crystal [3]
C30B 13/32
Mechanisms for moving either the charge or the heater [3]
C30B 13/34
characterised by the seed, e.g. by its crystallographic orientation [3]
C30B 15/00
Single-crystal growth by pulling from a melt, e.g. Czochralski method (under a protective fluid C30B 27/00) [3]
C30B 15/02
adding crystallising materials or reactants forming it in situ to the melt [3]
C30B 15/04
adding doping materials, e.g. for n–p-junction [3]
C30B 15/06
Non-vertical pulling [3]
C30B 15/08
Downward pulling [3]
C30B 15/10
Crucibles or containers for supporting the melt [3]
C30B 15/12
Double crucible methods [3]
C30B 15/14
Heating of the melt or the crystallised materials [3]
C30B 15/16
by irradiation or electric discharge [3]
C30B 15/18
using direct resistance heating in addition to other methods of heating, e.g. using Peltier heat [3]
C30B 15/20
Controlling or regulating (controlling or regulating in general G05) [3]
C30B 15/22
Stabilisation or shape controlling of the molten zone near the pulled crystal; Controlling the section of the crystal [3]
C30B 15/24
using mechanical means, e.g. shaping guides (shaping dies for edge-defined film-fed crystal growth C30B 15/34) [3]
C30B 15/26
using television detectors; using photo or X-ray detectors [3]
C30B 15/28
using weight changes of the crystal or the melt, e.g. flotation methods [3]
C30B 15/30
Mechanisms for rotating or moving either the melt or the crystal (flotation methods C30B 15/28) [3]
C30B 15/32
Seed holders, e.g. chucks [3]
C30B 15/34
Edge-defined film-fed crystal growth using dies or slits [3]
C30B 15/36
characterised by the seed, e.g. its crystallographic orientation [3]
C30B 17/00
Single-crystal growth on to a seed which remains in the melt during growth, e.g. Nacken-Kyropoulos method (C30B 15/00 takes precedence) [3]
C30B 19/00
Liquid-phase epitaxial-layer growth [3]
C30B 19/02
using molten solvents, e.g. flux [3]
C30B 19/04
the solvent being a component of the crystal composition [3]
C30B 19/06
Reaction chambers; Boats for supporting the melt; Substrate holders [3]
C30B 19/08
Heating of the reaction chamber or the substrate [3]
C30B 19/10
Controlling or regulating (controlling or regulating in general G05) [3]
C30B 19/12
characterised by the substrate [3]
C30B 21/00
Unidirectional solidification of eutectic materials [3]
C30B 21/02
by normal casting or gradient freezing [3]
C30B 21/04
by zone-melting [3]
C30B 21/06
by pulling from a melt [3]
Single-crystal growth from vapours [3]
C30B 23/00
Single-crystal growth by condensing evaporated or sublimed materials [3]
C30B 23/02
Epitaxial-layer growth [3]
C30B 23/04
Pattern deposit, e.g. by using masks [3]
C30B 23/06
Heating of the deposition chamber, the substrate, or the materials to be evaporated [3]
C30B 23/08
by condensing ionised vapours (by reactive sputtering C30B 25/06) [3]
C30B 25/00
Single-crystal growth by chemical reaction of reactive gases, e.g. chemical vapour deposition growth [3]
C30B 25/02
Epitaxial-layer growth [3]
C30B 25/04
Pattern deposit, e.g. by using masks [3]
C30B 25/06
by reactive sputtering [3]
C30B 25/08
Reaction chambers; Selection of materials therefor [3]
C30B 25/10
Heating of the reaction chamber or the substrate [3]
C30B 25/12
Substrate holders or susceptors [3]
C30B 25/14
Feed and outlet means for the gases; Modifying the flow of the reactive gases [3]
C30B 25/16
Controlling or regulating (controlling or regulating in general G05) [3]
C30B 25/18
characterised by the substrate [3]
C30B 25/20
the substrate being of the same materials as the epitaxial layer [3]
C30B 25/22
Sandwich processes [3]
C30B 27/00
Single-crystal growth under a protective fluid [3]
C30B 27/02
by pulling from a melt [3]
C30B 28/00
Production of homogeneous polycrystalline material with defined structure [5]
C30B 28/02
directly from the solid state [5]
C30B 28/04
from liquids [5]
C30B 28/06
by normal freezing or freezing under temperature gradient [5]
C30B 28/08
by zone-melting [5]
C30B 28/10
by pulling from a melt [5]
C30B 28/12
directly from the gas state [5]
C30B 28/14
by chemical reaction of reactive gases [5]
C30B 29/00
Single crystals or homogeneous polycrystalline material with defined structure characterised by the material or by their shape [5]

Note(s)

  • In groups C30B 29/02-C30B 29/54, in the absence of an indication to the contrary, a material is classified in the last appropriate place.
  • Attention is drawn to Note (3) after the title of section C, which Note indicates to which version of the periodic table of chemical elements the IPC refers.
C30B 29/02
Elements [3]
C30B 29/04
Diamond [3]
C30B 29/06
Silicon [3]
C30B 29/08
Germanium [3]
C30B 29/10
Inorganic compounds or compositions [3]
C30B 29/12
Halides [3]
C30B 29/14
Phosphates [3]
C30B 29/16
Oxides [3]
C30B 29/18
Quartz [3]
C30B 29/20
Aluminium oxides [3]
C30B 29/22
Complex oxides [3]
C30B 29/24
with formula AMeO3, wherein A is a rare earth metal and Me is Fe, Ga, Sc, Cr, Co, or Al, e.g. ortho ferrites [3]
C30B 29/26
with formula BMe2O4, wherein B is Mg, Ni, Co, Al, Zn or Cd and Me is Fe, Ga, Sc, Cr, Co, or Al [3]
C30B 29/28
with formula A3Me5O12, wherein A is a rare earth metal and Me is Fe, Ga, Sc, Cr, Co or Al, e.g. garnets [3]
C30B 29/30
Niobates; Vanadates; Tantalates [3]
C30B 29/32
Titanates; Germanates; Molybdates; Tungstates [3]
C30B 29/34
Silicates [3]
C30B 29/36
Carbides [3]
C30B 29/38
Nitrides [3]
C30B 29/40
AIIIBV compounds [3]
C30B 29/42
Gallium arsenide [3]
C30B 29/44
Gallium phosphide [3]
C30B 29/46
Sulfur-, selenium- or tellurium-containing compounds [3]
C30B 29/48
AIIBVI compounds [3]
C30B 29/50
Cadmium sulfide [3]
C30B 29/52
Alloys [3]
C30B 29/54
Organic compounds [3]
C30B 29/56
Tartrates [3]
C30B 29/58
Macromolecular compounds [3]
C30B 29/60
characterised by shape [3]
C30B 29/62
Whiskers or needles [3]
C30B 29/64
Flat crystals, e.g. plates, strips, disks [5]
C30B 29/66
Crystals of complex geometrical shape, e.g. tubes, cylinders [5]
C30B 29/68
Crystals with laminate structure, e.g. "superlattices" [5]
C30B 30/00
Production of single crystals or homogeneous polycrystalline material with defined structure characterised by the action of electric or magnetic fields, wave energy or other specific physical conditions [5]

Note(s)

  • When classifying in this group, classification is also made in groups C30B 1/00-C30B 28/00 according to the process of crystal growth.
C30B 30/02
using electric fields, e.g. electrolysis [5]
C30B 30/04
using magnetic fields [5]
C30B 30/06
using mechanical vibrations [5]
C30B 30/08
in conditions of zero-gravity or low gravity [5]
After-treatment of single crystals or homogeneous polycrystalline material with defined structure [5]
C30B 31/00
Diffusion or doping processes for single crystals or homogeneous polycrystalline material with defined structure; Apparatus therefor [5]
C30B 31/02
by contacting with diffusion materials in the solid state [3]
C30B 31/04
by contacting with diffusion materials in the liquid state [3]
C30B 31/06
by contacting with diffusion material in the gaseous state (C30B 31/18 takes precedence) [3]
C30B 31/08
the diffusion materials being a compound of the elements to be diffused [3]
C30B 31/10
Reaction chambers; Selection of materials therefor [3]
C30B 31/12
Heating of the reaction chamber [3]
C30B 31/14
Substrate holders or susceptors [3]
C30B 31/16
Feed and outlet means for the gases; Modifying the flow of the gases [3]
C30B 31/18
Controlling or regulating [3]
C30B 31/20
Doping by irradiation with electromagnetic waves or by particle radiation [3]
C30B 31/22
by ion-implantation [3]
C30B 33/00
After-treatment of single crystals or homogeneous polycrystalline material with defined structure (C30B 31/00 takes precedence) [5]
C30B 33/02
Heat treatment (C30B 33/04, C30B 33/06 take precedence) [5]
C30B 33/04
using electric or magnetic fields or particle radiation [5]
C30B 33/06
Joining of crystals [5]
C30B 33/08
Etching [5]
C30B 33/10
in solutions or melts [5]
C30B 33/12
in gas atmosphere or plasma [5]
C30B 35/00
Apparatus in general, specially adapted for the growth, production or after-treatment of single crystals or a homogeneous polycrystalline material with defined structure [5]