SYNTHESIS BY PULSED-LASER DEPOSITION OF METALLIC NANOCLUSTERS EMBEDDED IN AN AMORPHOUS HOST

Alternate ablation of metallic (Bi, Cu, Fe) and insulator (Al2O3) targ ets in vacuum have been used to produced nanocomposite films by pulsed laser deposition. The optical properties of the films are studied dur ing growth by in situ reflectivity measurements, which are also used t o control the process. The structure of the films is characterised by high resolution transmission electron microscopy. The results show tha t films with metallic nanocrystals 1.5-5.0 nm in diameter and high ref ractive index can be easily produced, the size and in-depth distributi on being easily controlled through the number of pulses in the metalli c and host targets, respectively. The growth mechanism, the role of an argon environment during growth, and the stability of the clusters up on annealing, are discussed. (C) 1998 Elsevier Science B.V.