Cathodoluminescence microanalysis of diamond nanocrystals in fused silicon dioxide

Abstract

MeV carbon ion implantation followed by thermal annealing in a hydrogen-containing atmosphere produces a layer of diamond nanocrystals within fused quartz (SiO2). Cathodoluminescence (CL) microanalysis in a scanning electron microscope has revealed at least three previously unreported low intensity CL emissions from carbon implanted and thermally annealed fused SiO2. The CL emissions are observed at 2.78 eV [full width at half maximum (FWHM) of 0.08 eV], ∼3 eV (FWHM of 0.4 eV), and 3.18 eV (FWHM of 0.11 eV). The peak widths and energies of these emissions are incompatible with any known defects associated with the silicon dioxide host lattice. Nondestructive depth resolved CL microanalysis investigations confirm that these CL emissions originate from the near-surface region, consistent with their association with the layer of diamond nanocrystals.