Formation of nanoclusters in Au-implanted bismuth tellurite

Bismuth tellurite single crystals have been implanted with 800 keV Au+ ions to a fluence of 1 x 10(16) cm(-2) at room temperature. Heat treatments of the samples were performed at temperatures ranging from 400 degreesC to 700 degreesC for 2 h at ambient atmosphere in a conventional furnace. Strong a bsorption maxima in the range from 600 to 630 nm and an intense blue-green color in the optical absorption spectra indicate the formation of Au-cluste rs. The average cluster radii were estimated to be between 3 and 4 nm for a nnealings performed at 500 degreesC and 600 degreesC. Rutherford backscatte ring (RBS)/channeling studies reveal that at temperatures suitable for the formation of nanoclusters no recrystallization takes place. On the other ha nd, a significant lattice recovery is observed for annealing at 400 degrees C for which no cluster formation was observed. (C) 2001 Elsevier Science B, V. All rights reserved.