Study of Structural and Optoelectronic Properties of Thin Films Made of a Few Layered WS₂ Flakes.

ABSTRACT: We report a surfactant-free exfoliation method of WS₂ flakes combined with a vacuum filtration method to fabricate thin (<50 nm) WS₂ films, that can be transferred on any arbitrary substrate. Films are composed of thin (<4 nm) single flakes, forming a large size uniform film, verified by AFM and SEM. Using statistical phonons investigation, we demonstrate structural quality and uniformity of the film sample and we provide first-order temperature coefficient ?, which shows linear dependence over 300-450 K temperature range. Electrical measurements show film sheet resistance R_S = 48 M?/? and also reveal two energy band gaps related to the intrinsic architecture of the thin film. Finally, we show that optical transmission/absorption is rich above the bandgap exhibiting several excitonic resonances, and nearly feature-less below the bandgap.

SUBMITTER: Lapinska A 

PROVIDER: S-EPMC7727660 | biostudies-literature | 2020 Nov

REPOSITORIES: biostudies-literature