Precipitation of group V elements and Ge in SiO2 and their drift in a temperature gradient

Abstract

It is shown that P, Sb, and Ge ions implanted in SiO₂ precipitate into spherical clusters of up to 1000 Å diameter when heat treated in an oxygen‐free ambient. This behavior is similar to that reported earlier for As implants. The clusters can be detected directly by transmission electron microscopy, or inferred from the unidirectional drift of the doped zone in a temperature gradient. Boron, a representative of group III, is the only element among those tested that does not migrate in a ∇T, suggesting the absence of phase separation.