High performance photodetector based on graphene/MoS2/graphene lateral heterostrurcture with Schottky junctions

Graphene and other two-dimensional (2D) materials have emerged as promising materials for future optoelectric applications. However, low detectivity of two-dimensional materials based photodetector inhibits their application. Here, we report a lateral graphene/MoS2/graphene (GMG) heterostructure photodetector which was synthesized by chemical vapor disposition (CVD). Electrical measurement shows that on/off ratio is up to 10 6 and two opposing Schottky junctions are connected in a series. Photocurrent mapping indicates that the Schottky junctions formed by graphene and MoS2 are the core part of the device, where photoexcited electron-hole pairs are spontaneously and rapidly separated. The responsivity is more than 2 × 10 3 m A / W and the maximum specific detectivity is as high as 10 13 J o n e s , respectively. This special design for the 2D materials based photodetector with high detectivity gives great potential for future application in nano-optoelectronic devices.