Gettering of metal impurities to cavities formed by hydrogen and helium implantation in silicon

Abstract

Implantation conditions necessary to form a sub-surface depth layer containing cavities by H+ and He+ implantation into Si were determined and discussed. Ion energy and fluence in the two cases were chosen to meet the criteria necessary to form a gettering layer located deeper than the active regions in submicro devices. The results obtained allowed us to determine that under specified conditions for H+ and He+ implantation into Si, a rather thick (Δz∼0.3–0.4μm) layer can be formed which contains the impurity gettering sites. The gettering behaviour for several transition metals, such as Au, Cu, Co and Fe was discussed.