Characterisation of Ge nanocrystals in co-sputtered Ge+SiO2 system using raman spectroscopy, RBS and TEM

Abstract

The high resolution transmission electron microscopy (HRTEM), Rutherford backscattering spectroscopy (RBS) and Raman spectroscopy results of germanium nanocrystals embedded in SiO2 synthesized by rapid thermal annealing (RTA) was presented. HRTEM reveals that annealing temperatures below 800°C produce fewer and smaller Ge nanocrystals compared to those produced at 800°C. Above 800°C, the nanocrystals formed have a wide range of size distribution. Therefore the optimum temperature is at 800°C to have uniformly sized and regularly spaced nanocrystals. RBS was performed to establish the Ge distribution in the SiO2 matrix during annealing.