The dependences of diffusion coefficient of As, DAs, upon total As concentration, CT, and the relationships between CT and resistivity ρ for several diffusion temperatures are experimentally obtained for the As diffusion into p-type Si from doped polycrystalline-Si sources in the temperature range 850-1050°C. It is found that the relationship between CT and ρ is dependent upon diffusion temperature for CT above 1020 cm-3. The relationship between CT and electrically active As concentration at diffusion temperature, CA, i.e., CT=CA+(3. 2×10-6/n3i) C4A can be obtained, assuming that only electrically active As is mobile and is diffused by the single-level vacancy mechanism, and using the experimental result that the dependence of DAs/Di (Di is the intrinsic diffusion coefficient of As) upon CT/ni (n i is the intrinsic electron concentration) is not influenced by diffusion temperature. Using the above equation, it is found that the relationship between CA and ρ is independent of diffusion temperature, even for CA above 1020 cm-3, and can be approximated for CA above 1020 cm-3 by an empirical equation: ρ=8.7×104 C-2/5 A.
ASJC Scopus subject areas
- Physics and Astronomy(all)