In situ transmission electron microscopy study on the formation and evolution of germanium nanoclusters and nanoparticles in silicon oxide matrix

A systematic in situ transmission electron microscopy study was carried out on the formation and evolution of germanium (Ge) nanoclusters and nanoparticles in a structure consisted of a Ge plus silicon oxide or Ge plus germanium oxide layer sandwich between two SiO2 layers. Nanoclusters were observed in the Ge plus silicon oxide and the Ge plus germanium oxide samples when irradiated with an electron beam current with unheated substrate. Nanoparticles were observed in the Ge plus silicon oxide samples under electron beam irradiation with the substrate heated to 250 °C. The growth mechanism of the nanoparticles was well described by the classical model.