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

In this work, a system of embedded Ge nanoclusters (NCs) has been fabricated inside a thermally grown SiO x 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 SiO x surface. This can be achieved by choosing the proper fluence and energy. Thirty kilo electron volts Ge ions have been implanted into a SiO x matrix (thermally grown) on Si(100) substrate. Ge concentration has been varied by choosing three different fluences (2.5 × 10 15 , 5 × 10 15 and 1 × 10 16 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.