Microstructural evolution of {113} rodlike defects and {111} dislocation loops in silicon-implanted silicon

Abstract

Recent study indicated that transient enhanced diffusion in implanted silicon is attributed to {113} rodlike defects. We have used plan-view and cross-sectional transmission electron microscopy to study the microstructural evolution of {113} rodlike defects as well as their transition to {111} dislocation loops in heat treatment of Si-amorphized silicon. We found that {113} rodlike defects undergo three stages of change during postimplantation anneals; accumulation of point defects to form homogeneous circular interstitial clusters, growth of these clusters along the 〈110〉 direction in a {113} habit plane, and dissolution into the matrix. We observed that the nucleation of {111} dislocation loops at the amorphous/crystalline interface lags behind that of the {113} defects and occurs while the latter grow and/or dissolve. This suggests that there is a period when {113} defects release interstitial point defects before the {111} dislocation loops nucleate from matrix. The {113} defects were found to disappear completely at 900 °C for 120 s, but the {111} dislocation loops disappear at 1100 °C for 60 s.