Internal electric field formation in insulators under high-flux negative-ion implantation

Ion-flux-dependent nanoparticle formation is observed in silica glasses dur ing high-flux 60 keV Cu- implantation. Under the high-flux implantation, a strong electric field possibly forms in the glasses, and may affect the nan oparticle formation via the solute diffusion processes. In this study, the internal-field formation is evaluated based on a model of negative-ion impl antation, in which the difference in diffusion lengths between electrons an d holes induces held formation. The calculated fields remain at more than 2 000 nm in depth, although the ion range is similar to 45 nm. The fields dep end negligibly on the ion flux and the maximum value is 3.3 kV/cm. A mechan ism for creating the internal field and the possibility of high-flux effect s are discussed.