▎ 摘　　要

Reported here is the facile fabrication of all-reduced graphene oxide (RGO) field-effect-transistor (FET) on flexible substrates using a solo femtosecond laser direct writing (FsLDW) technology. By simply tuning the intensity of a femtosecond laser pulse, GO could be reduced in a controlled manner. Metallic and semiconducting RGO micro-patterns could be achieved by FsLDWunder high and moderate laser power, respectively, which enables direct writing of source/drain and gate electrodes, as well as semiconducting channel of a FET on flexible substrates in ambient condition. In this way, a metal-free all-RGO FET was successfully fabricated by FsLDW without the use of any masks or chemical reagents. FsLDW of all-RGO devices shows unique advantages in both facile fabrication and flexible integration of graphene-based micro-devices, revealing great potential for the development of future electronics.