▎ 摘　　要

Graphene-based optoelectronic devices, including reduced graphene oxide (RGO) devices, commonly exhibit a large dark current and low on/off ratio with high dark-power consumption and a small responsivity. In this study, semi-RGO-based infrared photodetectors were directly "written" by using lasers, which can exhibit a small dark current of approximately 12 mu A/cm(2) with a high responsivity of approximately 0.18A/W at 1,550 nm. Both the dark current and response speed can be tuned with GO as the gate dielectric in a field-effect transistor structure. These findings suggest the possibility of the three-dimensional "writing" of a micro-optoelectronic device or system with a low cost and high performance. (C) 2018 The Japan Society of Applied Physics