Optical changes were studied after the ArF excimer laser illumination (6.4eV, 193nm) of implanted (5MeV Si2+, 1015/cm2) high-purity material. The optical absorption was measured between 3eV (400nm) and 8eV (155nm), and was shown to reveal evidence of several well-defined absorption bands. A correlation of the bleaching behavior appeared to exist between the so-called D-band (7.15eV) and the well-known B2 band which had been attributed to O vacancies.

M.Verhaegen, J.L.Brebner, L.B.Allard, J.Albert: Applied Physics Letters, 1996, 68[22], 3084-6