XTEM study of low-energy ion-beam synthesized Ge nanoclusters inside SiOx matrix

In this work, a system of embedded Ge nanoclusters (NCs) has been fabricated inside a thermally grown SiOx matrix via a low-energy ion-implantation technique. The low-energy ion-implantation technique gives the flexibility to choose the number of ions to be implanted and depth at which the ions to be placed below the SiOx surface. This can be achieved by choosing the proper fluence and energy. Thirty kilo electron volts Ge ions have been implanted into a SiOx matrix (thermally grown) on Si(100) substrate. Ge concentration has been varied by choosing three different fluences (2.5 × 1015, 5 × 1015 and 1 × 1016 ions cm−2). Further, ex situ annealing was carried at 800°C under an inert atmosphere. Fluence-dependent distribution of Ge NCs post-annealing has been explained using Raman spectroscopy, photoluminescence spectroscopy (PL), Rutherford backscattering spectrometry (RBS) and cross-sectional transmission electron microscopy (XTEM) analysis.