Electrically active Fe-related defects in Czochralski n-type material were studied by means of deep-level transient spectroscopy and Hall-effect measurements. These Fe-related defects were identical to those found in float-zone n-type material. The results indicated that positively charged and negatively charged Fe states coexisted in Czochralski n-type material, and that only a small fraction of interstitial Fe atoms formed electrically active complexes. Such complexes were suggested to be intermediate states in an ongoing reaction leading to Fe precipitation. However, such precipitation in this material had not been confirmed.

In-diffusion and isothermal annealing of iron-related defects in Czochralski n-type silicon S.Tanaka, H.Kitagawa: Japanese Journal of Applied Physics - 2, 1998, 37[1A-B], L4-6