FORMATION OF OXYGEN-DEFICIENT TYPE STRUCTURAL DEFECTS AND STATE OF IONS IN SIO2 GLASSES IMPLANTED WITH TRANSITION-METAL IONS

The properties and concentrations of oxygen-deficient type structural defects in type III SiO2 glasses implanted with Ti+, Cr+, Mn+, Fe+, or Cu+ to doses from 0.5×1016 to 6×10016 ions/cm2 at an energy of 160 keV have been measured by using vacuum UV and EPR spectroscopies. An intense absorption band centered around 7.5 eV is observed in all the samples except for Cu-implanted ones and is attributed primarily to SiSi homo-bonds with the bond distance close to that of the Si2H6 molecule. The homo-bond and implanted ion concentrations are of the same order of magnitude in the implanted layers. An E′ type center associated with the homo-bond is observed in all the samples except for Cu-implanted ones. Anomalous behaviors of the Cu-implanted samples are attributed to the formation of Cu-colloids. An enhanced formation of metallic particles or colloids is suggested for the samples implanted with Cr, Mn or Fe to doses higher than ∼3×1016 ions/cm2. © 1990.