According to Fair's well-established model [Fai81] we express the diffusion coefficient as sum of several diffusivities, each accounting for impurity interactions with vacancies in different charge states (3.2-8). The individual diffusivities obey Arrhenius laws , values are summarized in Table 3.2-1. The intrinsic carrier concentration is calculated using (approximations to) Morin and Maita's [Mor54] empirical model (Table 3.2-2).