Method for preparing structured graphene on SiC substrate based on Cl2 reaction

Patent metadata

Field	Value
Publication number	US-9951418-B2
Application number	US-201214397633-A
Country	US
Kind code	B2
Filing date	Dec 31, 2012
Priority date	May 23, 2012
Publication date	Apr 24, 2018
Grant date	Apr 24, 2018

Abstract

Disclosed is a method for preparing structured graphene on a SiC substrate on the basis of Cl 2 reaction, the procedures are as follows: firstly, performing standard cleaning to a SiC sample chip; depositing a layer of SiO 2 on the surface of the SiC sample chip and engraving a figure window on the SiO 2 layer; then arranging the windowed sample chip in a quartz tube, introducing a mixed gas of Ar and Cl 2 into the quartz tube, reacting the bare SiC with Cl 2 for 3-8 min at 700-1100° C. to generate a carbon film; arranging the generated carbon film in Ar gas, annealing for 10-30 min at 1000-1200° C. to generate the structured graphene on the window on the carbon film. The method is simple and safe; the generated structured graphene has a smooth surface and low porosity and can be used for making microelectronic devices.

First claim

What is claimed is:

1. A method for preparing structured graphene on SiC substrate based on Cl 2 reaction, characterized in that said process comprises the following steps:
(1) performing cleaning to a SiC sample chip to remove contaminants on its surface;
(2) depositing a layer of SiO 2 with a thickness of 0.4-1.2 μm as a mask on the surface of the cleaned SiC sample chip by a Plasma Enhanced Chemical Vapor Deposition (PECVD) method;
(3) coating a layer of photoresist on the surface of the mask; photo-engraving a figure window on the mask in accordance with the shape of an expected device substrate to expose the SiC and form a structured pattern;
(4) placing the windowed sample chip in a quartz tube, heating the windowed sample chip to 700-1100° C. for 3-8 minutes as a mixed gas of Ar and Cl 2 is flowed into the quartz tube, and Cl 2 is reacted with the bare SiC to generate a carbon film;
(5) arranging the generated carbon film in Ar gas, annealing for 10-30 min under a temperature of 1000-1200° C., wherein the carbon film on the window is reconfigured to graphene so as to obtain a structured graphene.

2. The method for preparing structured graphene on SiC substrate based on Cl 2 reaction according to claim 1 , characterized in that said step (1) performing cleaning to a SiC sample chip is, firstly the SiC sample chip is soaked for 10-30 minutes by using reagent NH 4 OH+H 2 O 2 , then taken out and dried to remove the organic residue on the sample surface, and then the sample is soaked in reagent HCl+H 2 O 2 for 10-30 minutes, then taken out and dried to remove ionic contaminant.

3. The method for preparing structured graphene on SiC substrate based on Cl 2 reaction according to claim 1 , characterized in that in said step (2), the condition of depositing SiO 2 by PECVD method is, the flow rate of SiH 4 , N 2 O and N 2 is respectively 30 sccm, 60 sccm and 200 sccm, the pressure of a reaction chamber is 3.0 Pa, RF power is 100 W, the deposition temperature is 150° C. and the deposition time is 20-100 minutes.

4. The method for preparing structured graphene on SiC substrate based on Cl 2 reaction according to claim 1 , characterized in that in said step (2), the condition of depositing SiO 2 by PECVD method is, the flow rate of SiH 4 , N 2 O and N 2 is respectively 8-45 sccm, 35-450 sccm and 150-565 sccm, the pressure of a reaction chamber is 2-10 Pa, RF power is 30-220 W, the deposition temperature is 100-300° C. and the deposition time is 20-100 minutes.

5. The method for preparing structured graphene on SiC substrate based on Cl 2 reaction according to claim 4 , characterized in that in step (4), the flow rate of the flowed Ar and Cl 2 is respectively 95-98 sccm and 2-5 sccm.

6. The method for preparing structured graphene on SiC substrate based on Cl 2 reaction according to claim 5 , characterized in that in step (5), the flow rate of Ar when annealing is 25-100 sccm.

7. The method for preparing structured graphene on SiC substrate based on Cl 2 reaction according to claim 6 , characterized in that the SiC sample chip has a crystal type of 4H—SiC or 6H—SiC.

8. The method for preparing structured graphene on SiC substrate based on Cl 2 reaction according to claim 5 , characterized in that the SiC sample chip has a crystal type of 4H—SiC or 6H—SiC.

9. The method for preparing structured graphene on SiC substrate based on Cl 2 reaction according to claim 4 , characterized in that in step (5), the flow rate of Ar when annealing is 25-100 sccm.

10. The method for preparing structured graphene on SiC substrate based on Cl 2 reaction according to claim 4 , characterized in that the SiC sample chip has a crystal type of 4H—SiC or 6H—SiC.

11. The method for preparing structured graphene on SiC substrate based on Cl 2 reaction according to claim 1 , characterized in that in step (4), the flow rate of the flowed Ar and Cl 2 is respectively 95-98 sccm and 2-5 sccm.

12. The method for preparing structured graphene on SiC substrate based on Cl 2 reaction according to claim 11 , characterized in that in step (5), the flow rate of Ar when annealing is 25-100 sccm.

13. The method for preparing structured graphene on SiC substrate based on Cl 2 reaction according to claim 1 , characterized in that in step (5), the flow rate of Ar when annealing is 25-100 sccm.

14. The method for preparing structured graphene on SiC substrate based on Cl 2 reaction according to claim 1 , characterized in that the SiC sample chip has a crystal type of 4H—SiC or 6H—SiC.

Assignees

• Univ Xidian

Inventors

• Guo Hui
• Zhang Keji
• Zhang Yuming
• Deng Pengfei
• Lei Tianmin
• Zhang Fengqi

Classifications

• C01B32/186 Primary

  by chemical vapour deposition [CVD] · CPC title

• C01B32/188

  by epitaxial growth · CPC title

• C23C16/26 Primary

  Deposition of carbon only · CPC title