The diffusion of B into single crystals, from a BF2-implanted polycrystalline film deposited on the surface, was accurately modelled. The effective diffusivities of B in the monocrystalline substrate were extracted by using Boltzmann-Matano analyses, and the phenomenological model for B diffusivity was implemented in a computer simulation program. The model was applied to a range of furnace annealing conditions (800 to 950C, 0.5 to 6h) and BF2 doses ranging from 5 x 1015 to 2 x 1016/cm2 at 70keV. It was found that the diffusion parameters exhibited a complicated dependence upon the B composition (table 24).
A.Sultan, M.Lobo, S.Bhattacharya, S.Banerjee, S.Batra, M.Manning, C.Dennison: Journal of Electronic Materials, 1993, 22[9], 1129-36
Table 24
Diffusion Parameters for B in Si, as a Function of the B Composition
Concentration Range (/cm3) | Do(cm2/s) | Q(eV) |
less than 5.0 x 1018 | 0.0012848 | 2.6950 |
5 x 1018 to 1.4 x 1019 | 0.0001393(10[1.9280E-19]C) | 2.5222(10[5.7581E-21]C) |
1.4 x 1019 to 3.0 x 1019 | 4.8828 x 10-373(C 19.376) | 2.4735 x 10-10(C 0.5268) |
3.0 x 1019 to 4.0 x 1019 | 1.2226 x 10-90(C 4.8746) | 0.0069046(C 0.1444) |
4.0 x 1019 to 1.0 x 1020 | 8.0643 x 10295(C -14.8190) | 1.3329 x 107(C -0.3295) |
greater than 1.0 x 1020 | 0.3362 | 3.4260 |