Ion beam induced dissolution and precipitation of in situ formed Si-nanostructures in a-SiNx:H matrix

We report here the response of in situ formed Si-nanostructures embedded in Si-rich hydrogenated amorphous silicon nitride matrix to 100 MeV Ni8+ ions irradiation under normal incidence at room temperature. Prior to irradiation, Si-nanostructures are amorphous in nature having partial crystallinity. Irradiation with a fluence of 5 x 10(12) ions/cm(2) leads to dissolution of Si-nanostructures. Nevertheless, irradiation with a relatively higher fluence of 1 x 10(14) ions/cm(2) enhances the nucleation and leads to the formation of amorphous Si-nanostructures. The results are understood on the basis of intense electronic energy loss induced hydrogen desorption and consequent rearrangement of the amorphous network under thermal spike formalism of ion-material interaction. Published by Elsevier B.V.