▎ 摘　　要

NOVELTY - The method involves providing a carrier that comprises a catalytic metal surface, a carbon source, a hydrogen source and an inert carrier gas. Surface roughness and/or impurities content of the support surface are reduced. The catalytic surface is provided in a conditioned environment. The carbon source is provided in the conditioned environment at pressure that is less than 1000 Torr, and flow rate is less than 500 sccm. A graphene from carbon is synthesized by activation with the catalyst at predetermined time period to a conformal layer of graphene on the catalytic surface. USE - Method for synthesizing a graphene layer of a field-effect transistor, a photonic/optoelectronic device and a gas/liquid membrane. ADVANTAGE - The method enables using a material in a metal container that can prevent entry of solid particles from deposition on a graphene and allowing entry of gas to form the graphene, and adapting a cooling system that can avoid overheating of a clamping part of a chamber. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is also included for a graphene large layer. DESCRIPTION OF DRAWING(S) - The drawing shows a schematic view illustrating a method for synthesizing a graphene layer of a field-effect transistor. CVD-chamber (10) Furnace (30) Gas inlet (40) Metal container (50) O-shaped ring (60)