Multilayer MoS 2 Photodetector with Broad Spectral Range and Multiband Response

Abstract

As a typical 2-dimensional material, molybdenum disulfide (MoS 2 ) has atomic thickness in longitudinal size, showing unique optical and electrical properties. MoS 2 has become a research hotspot in the field of photodetection. The properties of MoS 2 devices are highly dependent on their material characteristics, device structures, and fabrication techniques. Therefore, their photoresponse characteristics may be determined by multiple physical effects, which contribute to the development of MoS 2 -based broadband photodetectors. Here, we present an experimental study on the broadband MoS 2 photodetector ranging from 410 to 1,550 nm, obviously wider than that of conventionally reported MoS 2 photodetectors. Our results indicate that the performance of the MoS 2 device is dependent on the fabrication procedures. Under the optimal process, the maximum responsivity is 33.75 A W −1 and the corresponding specific detectivity is 6.1 × 10 11 cm Hz 1/2 W −1 at 480-nm illumination. Through a series of electrical and optoelectronic experimental analysis, the working mechanisms of multiband photoresponse of the MoS 2 device are clarified.