It was noted that the Si particle detectors in devices for the high-luminosity LHC would suffer an extremely intense radiation field of mainly hadronic particles. The main radiation-induced deep defect centres in silicon, responsible for the increase in the dark current and corresponding noise, were the cluster-related defect levels E5 and E205a. This work confirmed the identification of the E5 level as being a tri-vacancy (V3). This defect transformed into the tri-vacancy-oxygen complex (V3O) above 200C. The defect concentrations were obtained by means of deep-level transient spectroscopy and thermally stimulated current technique performed on float zone, epitaxially grown and magnetic Czochralski silicon diodes, irradiated with 1MeV neutrons and 23GeV protons.

A Contribution to the Identification of the E5 Defect Level as Tri-Vacancy (V3). A.Junkes, I.Pintilie, E.Fretwurst, D.Eckstein: Physica B, 2012, 407[15], 3013-5