Dispersive parameters for complex refractive index of p- and n-type silicon from spectrophotometric measurements in spectral range 200–2500 nm

• Complex refractive indices of doped silicon samples are retrieved by analytical relations.
• Dispersive parameters of Wemple–DiDomenico dispersion model are compared.
• A dispersion model for the imaginary refractive index is investigated.
• As boron increases the real index and absorption coefficient decrease.
• As phosphor increases the real index decreases but absorption coefficient increases.

The spectral reflectance R(λ) and spectral transmittance T(λ) of p- and n-type silicon samples, having plane-parallel faces, are measured with a UV–vis–NIR spectrophotometer at room temperature. Measured data are introduced into analytical expressions to retrieve the complex refractive indices of silicon slabs across 200–2500 nm spectral range. The Wemple–DiDomenico dispersion model for real refractive index in the transparent region is used. Correlation between two atomic parameters and the dispersion constants of this dispersion model is established. Effects of doping on dispersion parameters, atomic parameters, the density of valence electrons, nv, coordination number, Nc, and the energy gap, Eg, are investigated. A dispersion model for the imaginary refractive index in the absorption region is investigated.