Structural phase transformation in ZnS nanocrystalline thin films by swift heavy ion irradiation
Abstract
Zinc sulfide (ZnS) thin films in zinc-blende (ZB) and wurtzite (W) phases have been fabricated by pulsed laser deposition. 150 MeV Ni ion beam irradiation has been carried out at different fluences ranging from 10(11) to 10(13) ions/cm(2) at room temperature for ion induced modifications. Structural phase transformation in ZnS from W to ZB phase is observed after high energy ion irradiation which leads to the decrease in bandgap. Generation of high pressure and temperature by thermal spike during MeV Ion irradiation along the ion trajectory in the films is responsible for the structural phase transformation. (C) 2010 Elsevier Ltd. All rights reserved