Ion implantation as an approach for tuning of electronic structure, optical, morphological and electrical transport properties of sputtered molybdenum disulfide thin films

Abstract

Molybdenum disulfide (MoS2) thin films have acquired increasing consideration in the field of low-dimensional electronics as device-active layers and also in hydrogen evolution reaction (HER) as catalysts in distinct electrochemical processes. Thus, for distinct applications, extensive scalable fabrication techniques with tunable MoS2 properties are significant. To possess tunable efficiency of various device applications at nanoscale it is significant to acquire control over the density of defects, although attaining with direct growth techniques remains a significant issue. Here we illustrate a robust and effective approach to tailor the density of defects using Au ion implantation. In the present work, we illustrate the scalable technique i.e. magnetron sputtering for the fabrication of MoS2 thin films, subsequently, ion implantation with 80 keV Au ions at a distinct fluence of 1 × 1015 and 5 × 1015 ions/cm2 was carried out. Striking deviations were remarked in nanostructure and depth distributions of the resultant thin films of MoS2. Pristine and ion implanted thin films were characterized to comprehend the morphological, electrical transport and electronic structure properties. The surface micrographs’ results revealed noteworthy alterations in the thin films’ surface roughness. The modifications induced by low energy Au ion implantation in core-level electronic structure and atomic bonding was probed by XPS and Raman spectroscopy technique. The electrical properties of these films were studied to demonstrate the scattering and conduction mechanisms. The present work contributes to the significant passage of tailoring 2D MoS2 thin films’ electronic structure, optical and morphological properties through doping and defects formation by low energy ion beam implantation to extend their practical device applications.