Excess Vacancy Generation by Silicide Formation in Si

Abstract

AbstractIt has been long recognized that excess point defects are generated when a metal silicide is formed on silicon. Since the common dopants diffuse in Si with the aid of both self-interstials and vacancies, these point defect perturbations will influence motion of diffusions that are in the adjacent vicinity. TiSi2 is known to enhance the concentration of vacancies and several mechanisms have been proposed for this effect. Recent literature has dealt with and rejected many of these ideas; however, some of the remaining few like film strain and lattice contraction upon silicidation have been the subject of state of the art experiments which has led to their rejection.It is the contention of this paper that by using the experimental data from this recent work and reinterpreting it, the model of volume contraction of the silicides as the cause for vacancy injection, still represents the most physically satisfying cause and therefore, was mistakenly rejected.