Ion implantation at elevated temperature, so-called hot implantation, was used to study nucleation and thermal stability of the defects. The MgO(100) single crystals were implanted with 30keV He ions at various temperatures, to doses ranging from 1014 to 1016/cm2. The implantation-introduced defects were subsequently studied by thermal He desorption spectroscopy and Doppler broadening positron beam analysis. The thermal He desorption spectroscopy study provided vital information on the kinetics of He release from the sample. Positron beam analysis, being sensitive to the open volume defects, provided complementary information on cavity evolution. The thermal He desorption spectroscopy study had shown that in most cases He release was characterized by the activation energy of 4.7eV with the maximum release temperature of 1830K. By applying first-order desorption model, the pre-exponent factor was estimated to be 4.3 x 1011/s.

A Hot Implantation Study on the Evolution of Defects in He Ion Implanted MgO(100). A.V.Fedorov, M.A.van Huis, A.van Veen: Nuclear Instruments and Methods in Physics Research Section B, 2002, 191[1-4], 452-5