Published online by Cambridge University Press: 03 September 2012
Zinc ion implanted silica with controlled thermal annealing has been investigated. Low temperature optical measurements indicate the presence of Zn clusters in the as-implanted silica. Optical spectra of the annealed sample under a reducing environment suggest Zn cluster and Zn metal colloid formation. The absorption peak at ∼5.3 eV may be due to the surface plasma absorption of Zn metal colloids in silica. The oxidized samples (10 and 6 x 1016 ions/cm2) show an absorption peak at ∼4.3 and ∼4.8 eV, respectively and imply ZnO quantum dot formation. The blueshift in exciton absorption can be attributed to the quantum confinement effects.