Atomic force microscopy of Au implanted in sapphire

Abstract

Ion implantation of gold into sapphire followed by annealing at 1100 °C leads to the formation of metal colloids. We report on the atomic force microscopy (AFM), infrared reflectance, and optical spectra for Au implanted in sapphire. The presence of the metal colloids is revealed in the optical spectra by the appearance of an absorption at 547.5 nm for the annealed sample, which we attribute to the surface plasmon resonance of Au colloids. The infrared spectra indicate that annealing Au-implanted sapphire at 1100 °C relaxes most of the ion-induced damage in the crystal. Tapping mode AFM has been applied to image the Au colloids embedded in the sapphire matrix. Colloids ranging in size from 10 to 30 nm were observed by AFM measurements. The shape of the colloids appear to be predominantly spherical.