INFLUENCE OF n-TYPE DOPANTS ON THE LATTICE LOCATION OF IMPLANTED p-TYPE DOPANTS IN Si AND Ge

The orientation dependence of the backscattering yield of 1.8-MeV carbon ions has been used to determine the lattice location of group III and V elements implanted into Si and Ge at 30 keV and ∼350°C. It is shown that the lattice location of p-type dopants is affected by the presence of n-type dopants in the substrate. For example, when T1 is implanted alone into Si a large interstitial component is observed. For a ``mixed'' T1 and As implantation, however, the substitutional T1 component is enhanced at the expense of the interstitial component.