Transient 210-nm absorption in fused silica induced by high-power UV laser irradiation.

Synthetic fused silica, exposed to high-power KrF excimer laser irradiation, shows the well-known induced absorption at 210 nm owing to E' center generation. Time-resolved absorption spectroscopy reveals that this induced absorption is transient in nature. The generation rate of E' centers depends strongly on the irradiation history, the OH content, and previous high-temperature processes. In order to explain the experimental observations, a nonabsorbing state of theE' center is postulated. The recovery of the induced optical absorption in high-OH fused silica is explained as a conversion from E' centers to these nonabsorbing centers.

[1]  E. Friebele,et al.  Oxygen-associated trapped-hole centers in high-purity fused silicas , 1979 .

[2]  J. E. Shelby,et al.  Radiation effects in hydrogen‐impregnated vitreous silica , 1979 .

[3]  R. Weeks,et al.  Relation Between E′ Centers and Hydroxyl Bonds in Silica , 1964 .

[4]  Kastner,et al.  Time-resolved photoluminescence in amorphous silicon dioxide. , 1987, Physical review. B, Condensed matter.

[5]  A. Edwards,et al.  Theory of the peroxy-radical defect in a -Si O 2 , 1982 .

[6]  E. J. Friebele,et al.  ESR studies of damage processes in X‐irradiated high purity a‐SiO2:OH and characterization of the formyl radical defect , 1983 .

[7]  R. Devine,et al.  Ultraviolet induced defect creation and annihilation in low‐temperature‐deposited SiO2 , 1989 .

[8]  D. C. Shaver,et al.  Effects of excimer laser irradiation on the transmission, index of refraction, and density of ultraviolet grade fused silica , 1989 .

[9]  R. A. Weeks,et al.  Paramagnetic Resonance of Lattice Defects in Irradiated Quartz , 1956 .

[10]  Tsai,et al.  Mechanism of intrinsic Si E'-center photogeneration in high-purity silica. , 1988, Physical review letters.

[11]  Y. Langevin,et al.  Radiation effects in SiO2 under electronic excitation , 1988 .

[12]  D. Griscom Characterization of three E'-center variants in X- and γ-irradiated high purity a-SiO2 , 1984 .

[13]  E. Dianov,et al.  Theory of H(I) Centers in Vitreous Silicon Dioxide , 1988 .

[14]  Noriaki Itoh,et al.  Transient optical absorption and luminescence induced by band-to-band excitation in amorphous SiO2 , 1988 .

[15]  David L. Griscom,et al.  Thermal bleaching of x-ray-induced defect centers in high purity fused silica by diffusion of radiolytic molecular hydrogen , 1984 .