First-principles computational methods were used to investigate the structural and electronic properties of the I4 self-interstitial aggregate. It was found that the defect was electrically active, and was identified with the B3 electron paramagnetic resonance centre. It was shown that its properties were consistent with the 0.29eV deep level transient signal that was observed following Si implantation. It was predicted that the defect would give rise to local modes which lay close to the Raman edge. On the other hand, the structure of the centre (figure 9) excluded it as being a nucleus for the aggregation of {311} defects.

Identification of the Tetra-Interstitial in Silicon. B.J.Coomer, J.P.Goss, R.Jones, S.Oberg, P.R.Briddon: Journal of Physics - Condensed Matter, 2001, 13[1], L1-7

Figure 9

Structure of I4 Defect in Si

(Shaded links are reconstructed bonds,

dotted links are [001] split interstitial pairs)