Depth dependence of {311} defect dissolution

Abstract

A deep band of {311} defects was created 520 nm below the silicon surface with a 350 keV Si implant followed by a cluster-forming rapid thermal anneal (800 °C, 1000 s). Chemical etching was used to vary the depth to the surface of the {311}-defect band. Afterwards, the defect dissolution was investigated at 750 °C for different times. Varying the depth in this fashion assures that only the depth and no other feature of the cluster distribution is changed. The {311} defects were analyzed by plan-view, transmission electron microscopy. We show that the dissolution time of the {311}-defect band varies linearly with depth, confirming that surface recombination controls the dissolution and is consistent with analogous observations of transient enhanced diffusion.