Variation in The Electronic and Microstructural Properties of Benzyl Viologen Treated MoS2/Si Heterojunction

Abstract

Molybdenum disulfide, being a low bandgap prototypical transition metal dichalcogenides, is widely used in modern devices for its outstanding material properties. An attempt has been made to modulate the properties of rapid thermally grown MoS2 thin films on silicon by varying the number of spin coatings of the benzyl viologen solution. The formation of grain-like morphology with the increase in number of spin coatings of BV solution were observed from FESEM images. AFM images were used to estimate the RMS roughness of BV treated MoS2 thin films. XRD pattern depicted the presence of the (002) characteristics peak around 2θ = 14.1°. Two Raman peaks has been observed around 389 cm−1 (E12g) and 408 cm−1 (A1g) for MoS2 films. The left shift in the A1g peak position is attributed to n-type nature in BV treated MoS2 thin films. Both XRD and Raman peak intensities are found to be deteriorated, with the number of coats of BV solution. The ideality factor, built-in voltage and carrier concentration have been calculated from I-V and C-V characteristics of MoS2/Si heterojunction. The ŋ and Vbi for six number of spin coatings are calculated as 1.35 and 0.35 V, respectively. The increase in the carrier concentration of MoS2 thin films has been observed for the rise in the number of spin coatings of BV solution.