Localised vibrational mode spectroscopy studies of self-interstitial clusters in neutron irradiated silicon

Abstract

The evolution of self-interstitial clusters in silicon (Si), produced by fast neutron irradiation of silicon crystals followed by anneals up to 750 C, is investigated using localised vibrational mode spectroscopy. A band at 582 cm À1 appears after irradiation and is stable up to 550 C was attributed to small self-interstitial clusters (I n , n 4), with the most probable candidate the I 4 structure. Two bands at 713 and 758 cm À1 arising in the spectra upon annealing of the 582 cm À1 band and surviving up to $750 C were correlated with larger interstitial clusters (I n , 5 n 8), with the most probable candidate the I 8 structure or/and with chainlike defects which are precursors of the {311} extended defects. The results illustrate the presence of different interstitial clusters I n , at the various temperature intervals of the material, in the course of an isochronal anneal sequence. As the annealing temperature increases, they evolve from first-order structures with a small number of self-interstitials (I n , n 4) for the temperatures 50 < T < 550 C, to second order structures (I n , 5 n 8) with a larger number of interstitials, for the temperatures 550 < T < 750 C. V C 2013 AIP Publishing LLC. [http://dx.

Di-interstitial defect in silicon revisited

“…[1][2][3][4][5][6][7][8][9][10][11] Investigating small self-interstitial clusters in Si is technologically important as they play fundamental role in many solid-state processes affecting the mechanical and electrical properties of the material. It is therefore necessary to control them as their formation can cause detrimental effects.…”