Estimation of optical parameters of silicon single crystals with different orientations

Optical properties of Si single crystals with different orientations (1 0 0) and (1 1 1) were investigated using spectrophotometric measurements in a spectral range of 200 nm to 2500 nm. The data of optical absorption revealed an indirect allowed transition with energy gap of 1.1 ± 0.025 eV. An anomalous dispersion in refractive index. The normal dispersion of the refractive index was discussed according to Wemple-DiDomenico single oscillator model. The oscillator energy E_o, dispersion energy E_d, high frequency dielectric constant ∈_∞, lattice dielectric constant ∈L and electronic polarizability α_e were estimated. The real ∈₁ and imaginary ∈₂ parts of dielectric constant were also determined.