ELECTRON PARAMAGNETIC RESONANCE OF SILICA GLASS IMPLANTED WITH TUNGSTEN

Abstract

One-millimeter thick discs of Russian commercial silica glasses of KV type are implanted with W+ ions at an energy of 200 keV and a fluency density from 10¹⁵ to 2x10¹⁷ ions/ cm². RBS shows a Gaussian distribution of W ions with a maximum concentration at 80 nm from the surface. In the optical spectrum of the silica glass studied in the present work, the absorption bands at 710 nm and 1100 nm are observed. They can be assigned to W ions as well as the EPR spectrum consisting of the asymmetric line with g_II =1.593 and g_±=1.754. TEM data indicate the formation of almost spherical particles about 3 nm in diameter for the sample implanted at 10¹⁶ ions/cm².