Interactions of ionhyphen;implantationhyphen;induced interstitials with boron at high concentrations in silicon

摘要

Ion implantation of Si (60 keV, 1times;1014/cm2) has been used to introduce excess interstitials into silicon predoped with high background concentrations of B, which were varied between 1times;1018and 1times;1019/cm3. Following posthyphen;implantation annealing at 740thinsp;deg;C for 15 min to allow agglomeration of the available interstitials into elongated lcub;311rcub; defects, the density of the agglomerated interstitials was determined by planhyphen;view transmission electron microscopy observation of the defects. We report a significant reduction in the fraction of excess interstitials trapped in lcub;311rcub; defects as a function of boron concentration, up to nearly complete disappearance of the lcub;311rcub; defects at boron concentrations of 1times;1019/cm3. The reduction of the excess interstitial concentration is interpreted in terms of boronhyphen;interstitial clustering, and implications for transienthyphen;enhanced diffusion of B at high concentrations are discussed. copy;1996 American Institute of Physics.