Program

P.17 -- Poster, IWTCP-3

Date: Wednesday, 29 July 2015

Time: 08h30 - 10h00

Dependence of Effective Diffusivities on Boron impurity Concentration in Simultaneous Diffusion Process in Silicon

Vu Ba Dung

Hanoi University of Mining and Geology, Vietnam

Diffusion of impurities such as boron in silicon material is the complex process that is controlled by intrinsic point defects (self-interstitials and vacancies). Due to the interaction between boron and the crystal lattice, the diffusion process of boron in silicon often gives rise to point defects, which diffuse simultaneously and interact with the boron. Thus, diffusion coefficient of boron and point defect is dependent on that interaction, diffusion coefficient of boron is called effective diffusion coefficient (effective diffusivity). The calculation of effective diffusivity is very difficult. However, using irreversible thermodynamic theory, the effective diffusion coefficient of boron (B), self-interstitial (I) and vacancy (V) in silicon are studied and discussed. The results showed that effective diffusivities of boron and point defect in silicon are dependent on concentration of B, I and V. The calculated results also showed that when B concentration is high, effective diffusivity of boron is increased and diffusivity of point defects are reduced strongly. Furthermore, high concentration of boron makes effective diffusivity of I and V become negative and diffusion process of point defects are backward diffusion in silicon.

Presenter: Vu Ba Dung