Study of Photo-Conductivity in MoS2 Thin Films Grown in Low-Temperature Aqueous Solution Bath

Abstract

An experimental study over the optical response of thin MoS2 films grownby chemical bath deposition (CBD) method is presented. As two important factors, theeffect of bath temperature and growth time are considered on the photocurrentgeneration in the grown samples. The results show that increasing the growth time leadsto better optical response and higher difference between dark and photocurrent. Forhigher bath temperatures the layer loses its uniformity and the current reduces. Betterperformance of optical response is obtained for t=90min and T=70oC. We also studiedthe effect of post-annealing on the performance and quality of thin films. The I-Vmeasurements show no current flow for annealed films because of rupture of the filmstructure. Temporal response of the films to light source ON and OFF states is alsostudied and the results showed relaxation of photocurrent after about several seconds.The importance of the MoS2 thin films obtained by CBD method is low-temperatureprocess and large area of fabricated layers which can be used in many applications.

Keywords

• transition metal dichalcogenide
• molybdenum disulfide
• chemical bath deposition
• photocurrent