Swift heavy ion irradiation induced modifications in electron beam deposited CdS thin films

Abstract

The field of tailoring the physio-chemical properties by the way of radiation leads to the immense opportunities in the domain of advanced photonics and optoelectronic devices. In the present contribution, 120 MeV silver ions (Ag9+) induce electronic excitations which instigate modifications in crystalline cadmium sulphide (CdS) thin films deposited via electron beam evaporation are examined. X-ray Diffraction (XRD) reveals that the peak intensity and FWHM get affected as a consequence of swift heavy ions (SHI) irradiation while crystal phase remains preserved even after irradiation. Raman analysis exhibits the asymmetry in the fundamental longitudinal optical (LO) phonon mode which is directly related to the surface defects, reduction in particle size, and amorphization after irradiation. Field emission scanning electron microscopy (FESEM) images exhibit the reduction in particle size followed by highly strained as-deposited samples get stabilize with the deposited energy. The spherical shaped nanoparticles are observed for as-deposited and irradiated films through atomic force microscopy (AFM) and also, declared the nano-grain formation as resulted from negative surface tension induced at higher fluences. Photoluminescence (PL) spectra indicate the electronic excitations inspired additional yellow band due to generation of ICd-Vcd Frenkel pair defects along with the green and red emission.