Comprehensive, physically based modelling of As in Si

An accurate knowledge of the behavior of Arsenic appearing at high concentrations during thermal processes is essential for today's CMOS technology so that As is the most widely used n-type Si dopant in ultralarge scale integrated circuits. In spite of the large amount of successful research work devoted to reproducing As kinetics in Si, the level of complexity reached by Si device fabrication technologies claims for a more comprehensive physical modelling that, based on fundamental parameters of some basic As configurations could simultaneously account for aspects such as diffusion, electrical deactivation and amorphization/recrystallization after As implantation and annealing among others. We have used the atomistic kinetic Monte-Carlo simulator DADOS to develop a consistent physical model for As that includes a limited set of AsV clusters of different sizes and energies. Through a detailed modelling of Fermi level effects, we will discuss the main features of As behavior in Si such as: (i) intrinsic and extrinsic As diffusion; (ii) electrical deactivation at high As concentrations; (iii) annealing of As implanted profiles; and (iv) other striking features such as the interstitial supersaturation induced by rapid electrical deactivation of very high As concentrations at low temperatures. Finally, in order to test the model, this has been implemented with DADOS and compared with experiments, showing a good agreement in all the cases.