Characterization of P+ implanted SiO2 powders

P-31 ions were implanted into high-purity SiO2 sphere powders of 20 similar to 30 mu m phi at 50keV energy with 1.5x10(17)/cm(2) dose utilizing a modified medium-current implanter and, for reference, into SiO2 plate at 200keV with 1.0x10(18)/cm(2) utilizing a conventional medium-current implanter. P doping profile was measured by 3D-SIMS with 0.5 mu m phi Cs+ primary beam. Buried high P-concentration region was revealed. Implanted structure was observed by XTEM, EPMA and mu-RHEED: tens-nm-diameter sphere-like balls of phospho-silicate glass were distributed around the projected range. The top surface was almost unchanged from the substrate and was so thick as to prevent P elusion into hot water.