Research on photoresponse characteristics of bilayer molybdenum disulfide field effect transistors

The field-effect transistors (FETs) have attracted much attention because of the unique properties of the layered MoS₂ nanosheet as an ideal channel material. The phototransistors based on the MoS₂ FET have advantages of high photoresponsivity, rapid and stable response. This paper is concerned with the fabrication of bilayer MoS₂ based FET and the research on the photoelectric characteristics of the devices. The effect of the optical power and gate voltage on the photoelectric properties of the device was researched through the contrast experiments. It has been achieved that the photocurrent increases with the increase of optical power at the same gate voltage and drain voltage. The photoresponsivity also been enhanced with the gate voltage increased. And the photoresponsivity of bilayer MoS₂ FET was enhanced more than 100 folds by using MoS₂/MoO₃ as the channel material. The results indicated that the MoS₂/MoO₃ nanosheets can be a promising heterostructure material to offer a compelling case for application in enhancing the photoresponse characteristics of MoS₂ transistors. These unique properties make the bilayer MoS₂ based FET to be a great potential candidate of the next generation optoelectronic devices, which have the trend of miniaturization and integration. (paper)