基于化学气相沉积法铜基大面积单晶双层石墨烯薄膜的快速生长

Rapid Growth of Large-Area Single-Crystal Double-Layer Graphene Film on Copper Substrate Based on Chemical Vapor Deposition

通过分段控制甲烷与氢气的流量比以及增加氧气的供应,使用低压化学气相沉积设备(LPCVD)、在40 min的生长时间内、在铜箔上生长出连续的高质量的单晶石墨烯薄膜。研究表明,双氧钝化的使用和调整甲烷与氢气的流量比可以达到石墨烯的最佳成核和生长速率,使得石墨烯可以在短时间内生长为连续的单晶薄膜;石墨烯基场效应晶体管(FET)展现了优良的电学特性,其空穴迁移率可达到4 347 cm~2/(V·s)。

In this study,continuous and single crystal graphene films on copper(Cu)are synthesized by low pressure chemical vapor deposition(LPCVD)in the growth time of 40 min with the meticulously modulation of the oxygen and carbon supply in multistages synthesis processing,and graphene properties dependence on the oxygen and carbon supply is investigated.Optical microscope,field emission scanning electron microscope(FESEM)and atomic force microscope(AFM)are employed for morphology characterization while the graphene films structure are measured by transmission electron microscope(TEM),selected area electron diffraction(SAED)and Raman spectrum.It is found that double oxygen passivation(with the oxygen passivation in both nucleation and growth stages)together with the optimal flow ratio of methane and hydrogen will lead to the balance between nucleation and graphene growth rate to accomplish continuous single crystal bilayer graphene films in short time.The remarkable properties difference between the graphene processed by single and double oxygen passivation as well as the strong properties dependence on the flow ratio of methane and hydrogen with double oxygen passivation indicate that the nucleation and growth of graphene domains can be properly modulated by the oxygen passivation and carbon supply.Moreover,the graphene-based field effect transistor(FET)reveals the superior hole mobility of 4347 cm~2/(V·s).Our study provides a simple LPCVD procedure to achieve high quality graphene film on Cu in short time.