Continuous single crystal growth of graphene

Patent metadata

Field	Value
Publication number	US-2018187331-A1
Application number	US-201615393464-A
Country	US
Kind code	A1
Filing date	Dec 29, 2016
Priority date	Dec 29, 2016
Publication date	Jul 5, 2018
Grant date	—

Abstract

Systems and methods for synthesizing continuous single crystal graphene are provided. A catalytic substrate is drawn through a chemical vapor deposition chamber in a first lengthwise direction while flowing a hydrogen gas through the chemical vapor deposition chamber in the same lengthwise direction. A hydrocarbon precursor gas is supplied directly above a surface of the catalytic substrate. A high concentration gradient of the hydrocarbon precursor at the crystal growth front is generated to promote the growth of a continuous single crystal graphene film while suppressing the growth of seed domains ahead of the crystal growth front.

First claim

1 . A method of synthesizing graphene comprising:
heating the interior of a chemical vapor deposition chamber to a temperature above 800° C.; drawing a catalytic substrate through the interior of the chemical vapor deposition chamber in a first lengthwise direction; flowing hydrogen gas through the chemical vapor deposition chamber in the same first lengthwise direction, the hydrogen gas being mixed with an inert gas; and introducing a hydrocarbon gas through an opening within the chemical vapor deposition chamber in a region immediately above the catalytic substrate, wherein the hydrocarbon gas and the hydrogen gas form a precursor gas mixture, and wherein the catalytic substrate reacts with the precursor gas mixture to form continuous single crystal graphene on the catalytic substrate while being drawn in the same direction as the flow of the hydrogen gas.

2 . The method of claim 1 wherein the flowing hydrogen gas comprises flowing the hydrogen gas through the chemical vapor deposition chamber at a flow of at least 15 cm/s.

3 . The method of claim 1 wherein the opening is disposed between 1 mm to 10 mm above the catalytic substrate.

4 . The method of claim 1 wherein the catalytic substrate comprises a polycrystalline substrate.

5 . The method of claim 1 wherein at least one of a flux of the hydrocarbon gas through the opening and a flow rate of the hydrogen gas through the chemical vapor deposition chamber is selected to produce a concentration gradient of the hydrocarbon gas at a growth front of the continuous single crystal graphene.

6 . The method of claim 1 , further comprising delaminating the continuous single crystal graphene from the catalytic substrate without a supporting polymer layer.

7 . The method of claim 1 wherein the hydrogen gas comprises from 1.5 to 3% of hydrogen in a noble gas.

8 . The method of claim 1 wherein the hydrocarbon gas comprises 0.35% or less of a hydrocarbon precursor in a noble gas.

9 . The method of claim 1 , further comprising maintaining a flux at the opening at 30 sccm or less.

10 . The method of claim 1 wherein the drawing rate of the catalytic substrate is between 1 cm/hr to 2.5 cm/hr.

11 . The method of claim 1 , further comprising:
initiating growth of the continuous single crystal graphene on a support adjacent an edge of the catalytic substrate; and continuing to draw the catalytic substrate through the chemical vapor deposition chamber and past the opening to form the continuous single crystal graphene on the catalytic substrate.

12 . The method of claim 1 wherein the hydrocarbon gas is selected from the group consisting of methane, ethane, propane, butane, pentane, hexane, heptane, octane, benzene, toluene, and combinations thereof.

13 . The method of claim 1 wherein the first lengthwise direction is perpendicular to an armchair termination edge of the continuous single crystal graphene.

14 .- 20 . (canceled)

Assignees

• Ut Battelle Llc

Inventors

• List Iii Frederick Alyious
• Stehle Yijing Y
• Vlassiouk Ivan V
• Smirnov Sergei N

Classifications

• C23C16/26

  Deposition of carbon only · CPC title

• C30B29/02

  Elements · CPC title

• C23C16/45563

  Gas nozzles · CPC title

• C30B25/14

  Feed and outlet means for the gases; Modifying the flow of the reactive gases · CPC title

• C30B25/025 Primary

  Continuous growth · CPC title