As one of the representatives of transition metal sulfides, Tungsten disulfide(WS2) inherits the characteristics of graphene such as high mobility, transparency and flexibility. At the same time, its wide band gap also makes up for the defect of graphene zero band gap, making it have a higher The switching characteristics of the device make it have a broader development prospect in the field of electronic devices. In this work, low-pressure chemical vapor deposition(CVD) was used to prepare a dense few-layer WS2 film. At the same time, in order to understand the photoelectric performance of the grown WS2, a photodetector based on WS2 was fabricated and its photoelectric performance was studied. Here, the response time and dark current recovery time of the photodetector based on CVD WS2 is very fast (within 200ms). After illumination, dark current of the device is stable near 7.5e-11A. Upon Vds = 0.1v, the maximum responsivity of the optoelectronic device is 9mA/W, the maximum EQE is 3%, and the maximum On/Off ratio is 750. The photoelectric performance of the photodetector based on WS2 from high to low in different wavelength is 405nm, 660nm and 520nm. In addition to preparing photodetectors, this method of synthesizing dense WS2 film could pave the way for designing Large area humidity or gas sensor to study its humidity sensitive and gas sensitive performance.

Zhiming Lin. Synthesis of Dense WS2 Film and Its Photoelectric Properties. Academic Journal of Engineering and Technology Science (2020) Vol. 3 Issue 4: 81-89. https://doi.org/10.25236/AJETS.2020.030409.

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