Speaker
Description
We fabricated a photodetector based on multilayer molybdenum disulfide ($MoS_2$) by micromechanical cleavage of a molybdenite crystal using a polyimide film. We deposited 40nm of gold by vacuum sputtering and copper tape was used for the contacts. Without any surface treatment, we achieved high responsivity at different incident optical power. The calculated responsivity are 2$3\mu AW^{-1}$ of incident optical power in the range between 400 and 800nm. For the responsivity measurement it was estimated that $MoS_2$ have a bandgap of 1.6eV, which lies between monolayer and multilayer films. The thickness of the $MoS_2$ thin film was determined by Raman spectroscopy evaluating the difference between the in plane $E^1_2g$ and out of plane $A_1g$ Raman modes. The measurement of IV curves indicated Ohmic contacts in respect to the Au regardless of the incident optical power. Our device fabrication was much simpler than previous reported devices and can be used to test the light absorption and luminescence capabilities of exfoliated $MoS_2$.
