RADIATION ANNEALING IN NICKEL AND COPPER BY 100 MEV IODINE IONS

Radiation annealing by 100 MeV 127I-ions is studied in pre-doped Ni and Cu samples through the defect production rate measurements below 10 K. The experimental results are analyzed by using a new model which describes the production and radiation annealing of two or more types of defects. The subthreshold recombination cross section and the concentration of doped-in defects are obtained for each type of defects. In Ni, the defect annihilation corresponding to the stage-I thermal annealing occurs during the I-ion irradiation with the subthreshold recombination cross section of 6.5×10-12 to 1.4×10-12cm2. In Cu, the stage-I defects are annihilated with the cross section of 4.6×10-13cm2. The large radiation annealing in Ni shows the contribution of the electron excitation by irradiating ions to the subthreshold recombination of defects through the electron-phonon interaction. © 1990, THE PHYSICAL SOCIETY OF JAPAN. All rights reserved.