Lattice location and stability of ion implanted Cu in Si

We report on the lattice location of ion implanted Cu in Si using the emission channeling technique. The angular distribution of $\beta^{-}$-particles emitted by the radioactive isotope $^{67}$Cu was monitored following room temperature implantation into Si single crystals and annealing up to 600°C. The majority of Cu was found close to substitutional sites, however, with a significant displacement, most likely 0.50(8) along the <111> directions towards the bond center position. The activation energy for the dissociation of near-substitutional Cu is estimated to be 1.8-2.2 eV.