Interstitial defects involving boron in irradiated silicon

Silicon containing high concentrations of boron has been irradiated with 2 MeV electrons at room temperature. Initially, substitutional boron atoms are displaced into interstitial sites, but with prolonged irradiation there is a further interaction between B(i) and an intrinsic defect which is believed to be the Si(i). A similar effect is found in n 0 -irradiated samples. A broad absorption band is observed in the latter samples which is not detected in e - -irradiated crystals. It is suggested that this band is associated with boron in highly disordered regions. The present results are discussed in relation to atom location studies which utilize back-scattering techniques.