GOLD NANOCLUSTER FORMATION IN SILICATE-GLASSES BY LOW FLUENCE ION-IMPLANTATION AND ANNEALING

Gold ions have been implanted (285 keV, 8 x 10(15) cm(-2)) into fused silica and nine other different silicate glasses (commercially availab le and laboratory prepared glasses). We have studied the influence of annealing processes up to 1080 degrees C for silica and 600 degrees C for the other glasses. Only after the highest annealing temperatures d o the samples display an optical absorption band peaked at a wavelengt h of about 520 nm, characteristic of surface plasmon resonance of gold nanoparticles. Differences in the gold concentration profiles have be en attributed to radiation enhanced diffusion and structural differenc es, Optical absorption spectra reflect structural differences. First t ransmission electron microscopy measurements showed that the gold prec ipitates were nearly spherical with diameters of a few nanometers.