Lattice site occupation of non-soluble elements implanted in metals

Abstract

Recent studies of the lattice location of different atomic species implanted in metals are reviewed. It has been found that the most important factor influencing the substitutionality of implanted atoms is the heat of solution ΔH^sol. Since the vacancy-impurity binding energy increases with increasing Δ H^sol for non-soluble systems which have a rather high positive heat of solution, the formation of vacancy-impurity complexes is a decisive mechanism of the impurity displacement from the substitutional lattice site. The vacancy-impurity interaction leads to some new effects such as:o

1. a)
   the dependence of the substitutional fraction on the substrate temperature during implantation and on the annealing temperature,
2. b)
   the anomalous change of the substitutional fraction as a function of the impurity concentration and
3. c)
   the improvement of the substitutionality due to postirradiation.