Method for located growing of big single crystal graphene on SiC substrate through point-seed way

Abstract

The invention relates to a method for located growing of big single crystal graphene on a SiC substrate through a point-seed way. The method comprises the following steps: (1) polishing and cleaning SiC; feeding into a growing furnace; pumping vacuum; increasing the temperature to be 1200 to 1300 DEG C; charging argon and hydrogen; increasing the temperature to be 1500-1600 DEG C; performing hydrogen etching; closing hydrogen after etching; decreasing the temperature to be 1400 to 1500 DEG C, and maintaining the temperature; decreasing the temperature to be 800 to 1100 DEG C under argon atmosphere; placing a superfine heat conducting probe on the SiC substrate to form a local undercooling point; charging carbon source gas and hydrogen, wherein an active carbon source obtained by the decomposing of the carbon source gas can preferentially grow into graphene seed crystal at the undercooling point; (2) enabling continuous growing of graphene using the seed crystal on the SiC substrate as the center under the condition that the temperature is 800 to 1100 DEG C, the pressure is 800 to 900mbar, and carbon source gas is supplied, so as to obtain big single crystal graphene; and (3) charging argon after the growth, and decreasing the temperature, thus obtaining the big single crystal graphene. The method is free of a metal substrate, and the grown big single crystal graphene can be directly applied to micro-electronic appliance without being transferred.

Description

technical field [0001] The invention relates to a new method for positioning and growing large-size single crystal graphene on a SiC substrate through a point seed crystal process, and belongs to the technical field of microelectronic materials. Background technique [0002] Graphene is composed of C atoms with sp 2 The hexagons composed of orbitals form a honeycomb-like monolayer of atomic two-dimensional crystals. In 2004, the team of Geim and Novoselov at the University of Manchester in the United Kingdom first used tape micromechanical exfoliation of highly oriented pyrolytic graphite to obtain two-dimensional graphene, breaking the previous conclusion that two-dimensional materials cannot exist independently. [0003] As a carbon-based material, graphene's specific two-dimensional structure determines that it can synthesize other dimensional carbon nanomaterials such as zero-dimensional fullerene, one-dimensional carbon nanotubes, three-dimensional graphite, and graphe...

AI Technical Summary

Problems solved by technology

Although adopting this method can obtain large crystal domains of graphene, the same as patent document CN103074878A and patent document CN104498902A, the damage and pollution problems caused by graphene in the transfer process cannot be avoided

[0009] Chinese patent document CN103204498A discloses a method for preparing epitaxial graphene by thermally cracking silicon carbide. The process of preparing epitaxial graphene by thermally cracking silicon carbide under the assistance of argon gas is improved on the basis of the method for preparing epitaxial graphene by silicon carbide. The perforated graphite cover above the heated graphite reduces the influence of air flow and temperature, and controls the evaporation rate of Si at the same time. Although this method can obtain a graphene film with better uniformity, it cannot control single nucleation on the substrate, and it is difficult to Large-sized single-crystal graphene is obtained, and there is a buffer layer, which reduces the performance of graphene

Images