Microstructure of high-energy O and Cu ion-implanted silica glasses

The microstructure of silica glasses which have been implanted with 1.0 MeV O and 1.8 MeV Cu ions and subsequently annealed at 1000 degreesC are examined by transmission electron microscopy (TEM). It is found that a high density of single crystal nanoparticles are formed in a buried layer around 0.8-1.7 mum in depth. In the case of the Cu-implanted sample, only single crystal Cu nanoparticles are observed. When the ratio of the implanted O to Cu ion is 0.5:1, single crystalline nanoparticles of Cu2O are observed at a deeper part of the buried layer, associated with the projected range of the implanted O ions. As the O ion dose increases up to a ratio of O to Cu like 1:1, single crystals of CuO are formed in the buried layer. The depth profile of Cu and the size distribution of the nanoparticles are affected by the O ion-implantation. (C) 2001 Elsevier Science B.V. Ah rights reserved.