Self-interstitial diffusion and clustering with impurities in crystalline silicon

In this work the diffusion of ion-beam-injected self-interstitials (Is) and their interaction with impurities in crystalline Si are presented. In particular, the I penetration into a molecular beam epitaxy grown Si structure was studied by means of diffusion effects induced on B spikes, analyzed by a developed simulation code. Trapping effects at sample-surface and bulk are evidenced and modeled. The B marker approach was extended to the two-dimensional (2D) I-diffusion occurring as a consequence of ion implantation through a sub-micron dimension patterned oxide mask. I-source size effects on the I penetration have been found and modeled, quantitatively describing the 2D I-diffusion. The I-substitutional carbon interactions have been also studied, showing the C ability to effectively retain Is. The I-trapping mechanism was quantitatively studied by the simulation code, showing that one I is able to deactivate about two C traps by means of I-trapping and C-clustering reactions. This C property was used to control the ion-implantation induced damage and, consequently, to completely suppress B transient enhanced diffusion. Finally, the interaction between I and B leading to the B agglomeration into small B-I clusters (BICs) has been experimentally investigated. BICs dissolution kinetics was studied at different temperatures, directly using experimental concentration profiles and an opportunely developed B-diffusion simulation code. The activation energy for BICs dissolution and the BICs stoichiometry are extracted and given.