METHODS OF FORMING GRAPHENE SINGLE CRYSTAL DOMAINS

Luigi Colombo

Patent

Atlas literature

Patent

US 10,072,355

METHODS OF FORMING GRAPHENE SINGLE CRYSTAL DOMAINS

Luigi Colombo

Claims

Claims define the patent's legal scope. Independent claims stand alone; dependent claims (nested) narrow them. Click a claim to expand its dependents.

7 independent · 28 dependent

1
IndependentCO₂hydrocarbon gas (working gas)metal substrate
A method of forming a graphene single crystal domain on a substrate comprising a metal, comprising: a) contacting the substrate with a passivating gas to thereby decrease the number of nucleating sites on the substrate by at least 50 % to thereby create a low nucleation site density substrate, wherein the passivating gas comprises 02, sulfur, selenium, or a combination thereof, and wherein the passivating gas is provided at a pressure of from 1 x 10- 3 to 760 Torr; and b) contacting the low nucleation site density substrate with a working gas at a ﬁrst elevated temperature, wherein the working gas is provided at a pressure of from 1 x 10-6 Torr to 0.1 Torr, and wherein the working gas comprises a hydrocarbon gas; thereby forming a graphene single crystal domain on the low nucleation site density substrate. Currently amended
1. 2
  Dependent← claim 1metal foil substrate
  The method of claim 1, wherein the substrate comprises a metal foil. Original
2. 3
  Dependent← claim 1
  The method of claim 1, wherein the substrate comprises a dielectric substance coated with a metal. Withdrawn
3. 4
  Dependent← claim 1
  The method of claim 1, wherein the substrate comprises a wafer coated with a metal. Withdrawn
4. 5
  Dependent← claim 1
  The method of claim 1, wherein the method further comprises an annealing step before said contacting steps. Original
5. 11
  Dependent← claim 1
  11. The method of claim 1, wherein the substrate is contacted with the passivating gas for from 1 second to 20 minutes. Original
6. 12
  Dependent← claim 1
  The method of claim 1, wherein the passivating gas is ﬂ owed at a rate of from I to 10,000 s ecm. Original
7. 14
  Dependent← claim 1
  The method of claim 1, wherein the substrate is contacted with the passivating gas at a temperature of at least 20 °C. Original
8. 16
  Dependent← claim 1O₂
  The method of claim 1, wherein the passivating gas comprises 02. Previously presented
9. 17
  Dependent← claim 1
  The method of any claim 1, wherein the substrate is contacted with the working gas for from 1 to 800 minutes. Original
10. 18
  Dependent← claim 1
  The method of claim 1, wherein the working gas is ﬂowed at a rate of from 1 to 10,000 s ecm. Original
11. 20
  Dependent← claim 1
  The method of claim 1, wherein the ﬁrst elevated temperature is from 300 ° C to 1080 °C. Original
12. 22
  Dependent← claim 1hydrocarbon working gas (ethylene, acetylene, methane, benzene, toluene, ethane, hexane, heptanes, octane)
  The method of claim 1, wherein the working gas comprises one or more of the following: ethylene, acetylene, methane, benzene, toluene, ethane, hexane, heptanes, and octane. Previously presented
13. 23
  Dependent← claim 1CH₄
  The method of claim 1, wherein the working gas comprises methane. Withdrawn
14. 24
  Dependent← claim 1
  The method of claim 1, wherein the number of nucleation sites is decreased by at least 75 %. Original
15. 25
  Dependent← claim 1
  The method of claim 1, wherein the density of nucleation sites on the low nucleation density substrate is less than 1000 mm -2. Original
16. 26
  Dependent← claim 1
  The method of claim 1, wherein the density of nucleation sites on the low nucleation density substrate is less than 100 mm -2. Original
17. 27
  Dependent← claim 1Cu
  The method of claim 1, wherein the substrate comprises copper. Withdrawn
18. 30
  Dependent← claim 1C
  The method of claim 1, wherein the graphene single crystal domain is at least 100 micrometers in size. Original
19. 31
  Dependent← claim 1C
  The method of claim 1, wherein the graphene single crystal domain is at least 1 centimeter in size. Previously presented
20. 32
  Dependent← claim 1
  The method of claim 1, wherein the graphene single crystal domain density on the substrate is 100 mm-2 or less. Original
21. 33
  Dependent← claim 1C
  The method of claim 1, wherein the graphene single crystal domain is dendritic in shape. Original
13
Independent
Canceled
15
Independent
Canceled
19
Independent
Canceled
21
Independent
Canceled
34
IndependentChydrocarbon gas (working gas)Cu
A method of forming a graphene single crystal domain, comprising: contacting a surface of an oxygen rich substrate having nucleation sites with a working gas at an elevated temperature, wherein the surface of the oxygen rich substrate comprises 10-2 atomic % oxygen or more; wherein the oxygen rich substrate comprises a metal; wherein the working gas comprises a hydrocarbon gas; wherein the density of nucleation sites on the surface of the oxygen rich substrate is less than 100 mm -2; thereby forming a graphene single crystal domain on the surface of the oxygen rich substrate. Currently amended
35
Independent
Canceled

Worked examples

Embodiments described in the patent, grouped by the materials and process steps they use.

CVD graphene growth on copper substrates

example section example

7 materials2 process steps

Graphene single crystal domains were grown by CVD on oxygen-free copper (OF-Cu) and oxygen-rich copper (OR-Cu) foil substrates. The substrate was annealed in H2, then exposed to O₂ passivating gas to reduce nucleation site density, followed by growth in CH₄/H₂ at 1035°C. Growth parameters: PCH₄ = 5×10-3 Torr, PH₂ = 0.1 Torr, T = 1035°C, growth time 30 minutes. Large dendritic graphene single crystal domains up to centimeter scale were obtained on OR-Cu and OF-Cu(O) substrates. Characterization included SEM, Raman spectroscopy (including isotope-labeled mapping), LEEM/LEED, EBSD, and electrical transport measurements.

Materials

Materials described outside the worked examples.

hydrocarbon gas (working gas)

Working Gas Precursor

metal substrate

Substrate

Characterization

Measurements and analyses referenced in the patent, with their drawing references.

Raman spectroscopy

Raman Spectroscopy

SEM

Reported properties

Performance values and ranges asserted in the specification or claims.

Property	Value	Material
nucleation site density on low nucleation density substrate (claimed range)	≤ 1000 mm⁻²	C
graphene single crystal domain size (claimed minimum)	≥ 100 micrometer

Why these are connected

Related documents with shared materials, methods, properties, or citations.

METHODS OF FORMING GRAPHENE SINGLE CRYSTAL DOMAINS | Matter42 Literature