RBS/channeling, XRD and optical characterization of deep ion implantation into single crystalline SiO2

Ion implantation and subsequent annealing of 3.0 MeV Au⁺ into single crystalline c-plane (0001) hexagonal SiO₂ with different ion doses from 10¹⁴/cm² to 2×10¹⁶/cm² have been performed in JAERI/Takasaki. Rutherford Backscattering Spectrometry (RBS)/channeling, X-ray diffraction (XRD), pole figure of XRD and optical measurements are used to characterize these samples. We have found that the implanted gold is orientated even at quite a low dose, 1×10¹⁴/cm ², without heat treatment at high temperature, although the typical optical absorption band of 520 nm is not found before annealing. By sequential heat treatment at different temperatures, we have found that the optical absorption is highly dependent on annealing temperature. After annealing at 800°C for 10 hours, the absorption band is still not clear. However, after annealing at 1000°C for 5 hours, the samples display an optical absorption band peaked at 2.37 eV (523 nm), characteristic of surface plasmon resonance of gold nanoparticles. The average particle radius of Au colloid particles estimated from the absorption spectrum is about 4.2 nm. RBS/channeling analysis shows that the distribution of implanted Au displays a Gaussian profile both before and after annealing at different temperatures, and the ion range is in good agreement with the prediction from TRIM code