Study of defect formation/relaxation processes in Ge-doped SiO_2 by ArF laser irradiation

摘要

In Ge-doped SiO_2 defect centers induced by an ArF laser irradiation are investigated by electron spin resonance (ESR) measurements. Isochronal annealing have been carried out after the irradiation at 77 K in order to observe the formation and the relaxation processes of defects. Thermally induced decay of self-trapped hole (STH) and the formation of so-called "Ge(2)" centers are observed with increasing the temperature. The result suggests that holes are transferred from STH to Ge(2). It is observed that the relative concentration of germanium electron center (GEC) and GeE' do not change in the relaxation process from 210 K to 280 K.