The implantation of 1.1MeV Au ions into (100)-oriented single crystals, to doses of between 1016 and 1017/cm2, was carried out. It was found that this resulted in the formation of an implanted layer, with a thickness of 0.2, and in defect formation. In order to produce Au colloids in as-implanted samples, they were annealed in Ar, in H2 plus Ar, or in O2 plus Ar. It was noted that annealing above 1200C enhanced Au colloid formation and produced a Au surface plasmon resonance band. The bands for samples which had been annealed in the 3 types of atmosphere were found at 535nm (Ar), 524nm (H2+Ar), and 560nm (O2+Ar). The band positions of surface plasmons could be reversibly changed by additional annealing. On the basis of the temperature dependence of surface plasmon resonance changes, O vacancy mobility and Fe3+ ion reduction, Au colloid formation was deduced to be closely related to O vacancy movement at high temperatures.

A.Ueda, R.Mu, Y.S.Tung, D.O.Henderson, C.W.White, R.A.Zuhr, J.G.Zhu, P.W.Wang: Materials Science Forum, 1997, 239-241, 675-8