Dislocation formation and gettering mechanism of impurity atoms close to the active region

• Published in: Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms Beam interactions with materials and atoms, 1997-05, Vol.127, p.252-255
• Main Author: Gadiyak, G.V.
• Format: Article
• Language: English
• ISSN: 0168-583X; 1872-9584
• DOI: 10.1016/S0168-583X(96)00935-4

High-energy beams are starting to play an important role in silicon device technology. The most important potential use is the formation of CMOS profiled tubs by high-energy ion implantation which can give substantial economic advantages as well as enhanced device performance over the conventional furnace drive-in diffusion technology. Coupled with this technology is the use of MeV B beams to form gettering layers close to the active region. Here the gettering mechanism for iron (Fe) and theoretical model will be presented and compared with experimental data of Jacobson et al. The model consists of diffusion equations for Fe atoms, pairs (defect-boron), and point defects, the rate equation for boron atoms at the substitutional positions and also for structural damage: dislocation density and their size-radius of dislocation loops. The dislocations are the main gettering centers in which Fe atoms are precipitated during annealing. The results of numerical simulation modeling are in qualitative agreement with the experiments and the numerical fitting parameters are in the physically justifiable range.