CHARACTERIZATION OF DEFECTS IN SELF-ION IMPLANTED SI USING POSITRON ANNIHILATION SPECTROSCOPY AND RUTHERFORD BACKSCATTERING SPECTROSCOPY

The behavior of vacancy‐type defects and displaced Si atoms in Si(100) caused by self‐ion implantation has been investigated by variable‐energy positron annihilation spectroscopy and Rutherford backscattering spectroscopy/channeling. It is found that the recovery process of the defects strongly depends on the morphology of the implanted region. The divacancies produced by an implantation of 2×1014Si+⋅cm−2, which is less than the critical value required for amorphization, aggregate into large vacancy clusters by annealing at 300 °C. These vacancy clusters diffuse towards the surface at temperatures above 600 °C and anneal out at around 800 °C. The specimen implanted with 2×1015Si+⋅cm−2, in which a complete amorphization takes place in the damaged region, shows a different annealing characteristic. In the first stage (∼600 °C), the amorphous zone is transformed into crystalline material by solid phase epitaxial growth, although large vacancy clusters still remain. These agglomerate clusters continue to grow...