Effect of low energy ion beam irradiation on molybdenum disulfide films

Abstract

Molybdenum disulfide films were synthesized using drop casting technique. As prepared films were characterized using synchrotron XRD, Raman and UV-Visible spectroscopy. Films were irradiated using Argon beam having energy of 100 keV with electronic energy loss, Se∼44 eV/A. Different fluences varying from 1014 to 1016 ions/cm2 were used to irradiate films on the area of 1×1 cm2. Synchrotron X-ray diffraction technique with photons of energy 12.5 keV was used to study the structural changes induced in MoS2 films. An increase in crystallinity was observed for the lowest fluence of 5×1014 ions/cm2. Raman spectroscopy was performed to qualitatively determine the defects created using low ion beam. Raman spectrum of sample irradiated with the lowest fluence showed a red shift to indicate the annealed structure of MoS2 film. A blue shift in the Raman modes at higher fluence indicates the strain induced in the film with irradiation.