HYDROGEN CONTENT OF POLISHED GLASS SURFACES USING FORWARD RECOIL SPECTROSCOPY

The hydrogen content of fused silica and Zerodur glasses has been dete rmined using forward recoil spectroscopy (FRS). The glasses were polis hed with various compounds dispersed in water. The hydrogen depth prof iles consisted of a surface peak and a constant bulk hydrogen concentr ation. With a depth resolution of about 50 nm, FRS yielded surface hyd rogen concentrations of 1.7-4.5 x 10(15) and 5.1-7.6 x 10(15) H/cm2 fo r the fused silica and Zerodur glasses, respectively, and bulk concent rations of < 0.20 at.% H. For each of the polishing conditions studied , the surface hydrogen concentrations were significantly higher on the Zerodur glass than on the fused silica. This is taken as evidence tha t the Zerodur surfaces were hydrated more readily than those of fused silica.