Simulation of anti-reflecting dielectric films by the interference matrix method

Abstract In this work, the reflection coefficients of multilayer and gradient dielectric films are simulated. The basis of the conducted researches is the theoretical analysis of reflection coefficients for single and double layer films, which use the criterion of zero reflection coefficients for electromagnetic wave with a given wavelength. The specified length is selected based on the maximum spectral density data of the solar radiation. Numerical calculations were performed on the basis of the interference matrix method. Using this method, the reflection coefficients were calculated for the spectral range of electromagnetic radiation, in which photoelectric conversion of solar cells made of silicon occurs. The dependences of the reflection coefficients on the angle of incidence of the sun's rays are also calculated. Numerical methods were used to determine the average values of the reflection coefficients, taking into account the spectral density of solar radiation. Optimal values of the thicknesses of single and double layer films were found as well as gradient films with the linear law of change of the refractive index of the film material. The optimum values found were compared with the characteristics of the dielectric coatings used in solar power. Both traditional technologies based on CdTe and Cu(In,Ga)Se2 crystals and relatively new technologies based on the use of nanostructured films and porous silicon films have been considered. For these materials, the characteristics of the films are calculated, which provide values of reflection coefficients that are close to optimal values.