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We discuss the possibility of determining the electrophysical properties of semiconducting materials based on the determination of their optical constants by the method of broken total internal reflection. As the material for the total-internal-reflection prism it is proposed to use the experimental material, but with a much lower carrier concentration, The possibilities of the proposed method are demonstrated using as an example high-resistance silicon for the TIR prism and the experimental sample of n-type silicon.

The semiclassical relationships for the complex refractive index are used to find the regions of integration of the Kramers-Kronig dispersion relation required to yield the spectral dependence of the optical properties of semiconducting materials in the vicinity of the plasma resonance of the charge carriers with a prescribed accuracy. The refractive index n and the absorption coefficientκ of heavily doped Si in the vicinity of the plasma resonance of the charge carriers are determined by the Kramers-Kronig method and by the method of two media. The values of n andκ obtained by these methods are in good agreement with values calculated on the basis of the Drude-Lorentz semiclassical theory of dispersion.

Computations are carried out of the concentration distribution of inequilibrium charge carriers in semiconductor material with no restrictions on the excitation form — photo-excitation or excitation by electron beam, etc. — and likewise no restrictions on the spatial “map’ of excitation except for axial symmetry of the excitation function. Some particular cases are considered.

A nondestructive method of determining the parameters of epitaxial film systems is proposed based on a variational method of computing the coefficients of reflection and transmission of an electromagnetic wave in lamellarly inhomogeneous semiconductor structures. Structures of the type low-alloy film-transition layer-high-alloy substrate are considered with various prescriptions for varying the concentration of the alloying additives in the transition layer near the plasma resonance of the charge carriers in the substrate. Preliminary experimental investigations of the epitaxial N-N+ structures of silicon are in satisfactory agreement with computed data. The proposed method makes it possible to determine the thickness of the low-alloy layer and of the transition layer separately on the basis of the spectral dependence of the reflected radiation.

A method for determining the deposition depth of a p-n junction is described, which uses comparison of calculated and experimentally measured dependence of short circuit induced current on the energy of bombarding electrons. A formula for induced current is derived with consideration of recombination on the irradiated surface. Calculations are performed to permit study of the character of the short circuit induced current as a function of electron energy in structures with different recombination parameters and different p-n junction deposition depths.

The reflection coefficient R and the phase angleϕ of the reflected electromagnetic wave are calculated with an account of various scattering mechanisms (scattering by ionized impurity and by optical phonons) for wavelengths in the 2-mm range at room temperature. Simplified semiclassical equations for the complex reflection coefficient R* are shown to be valid. The equations are used to calculate R and ϕ for n-type GaAs as functions of the dimensionless frequencies y = ω/ωp and ωpτ. The experimental values of R and ϕ for n-type GaAs single crystals at 2.2 mm agree with the theoretical values, within the experimental error. The concentrations and mobilities determined from the experimental data agree well with the results of Hall measurements.