Thermal equilibrium concentrations and diffusivities of intrinsic point defects in silicon

Abstract

Recently, inherent defects in silicon crystal cause a serious problem resulting from the trend toward small scale and highly integrated circuits used in semiconductor devices. There is no doubt that intrinsic point defects in silicon are closely related to the formation mechanisms of these defects. Understanding the behavior of the point defects is thus extremely important. The equations for dopant diffusions and oxidation stacking faults in silicon, considering the intrinsic point defect concentrations as unknowns, are solved by mathematically self-consistent method and also the mechanisms of silicon self- and dopant-diffusions are determined. The thermal equilibrium concentrations and diffusivities of self-interstitials and vacancies in silicon, ∗CI, ∗CV, DI and DV are obtained as functions of the absolute temperature T. Consequently, the relations of ∗CI<(∗CI∗CV)1/2<∗CV and ∂Tln(DV)<∂Tln(DI) are derived for an arbitrary temperature.