Positron lifetime measurements are used to investigate positron trapping in silicon irradiated with protons at a high dose of 3.2×1017cm-2 and a lower dose of 3.6×1016cm-2, respectively. The irradiation-induced vacancy defects are mainly divacancies. During the irradiations, the divacancies in high dose samles have almost trapped hydrogens, while a part of the divacancies in low dose samples have not trapped hydrogensyet. In the measurements of the two warm-up of high dosed samples and the first warm-up of low dose samples, the further trapping of hydrogens into divacancies is observed., With increasing temperature the charge state of the divacancies decorated by hydrogens takes a transition from negative to neutral around 145K. With increasing the amount of the trapped hydrogens per divacancy, the lifetimes of the negatively charged divacancy and the neutral one are both shortened, while both their trapping cross sections are increased. The trapping of hydrogens into the negatively charged divacancies has no influence on the temperature dependence of its trpping cross sections.
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