Light trapping mechanism in one-dimensional (1D) photonic crystals for silicon-based solar cells

Abstract

In the present paper, the light trapping mechanism of one-dimensional (1D) photonic crystal of uniform symmetry for TE polarization is studied. The analysis of the forbidden bands, reflectivity, and group velocity is presented which are interdependent parameters and important to tune the desired optical properties. It is observed that the group velocity is the vanishing factor within the forbidden bands due to the increased optical path length of trapped photons. For solar cells, the use of 1D structure as bottom layer assures the prevention of electron and hole pair recombination for a longer time due to optical delay. We have compared the reflectivity of prepared multilayer (1D) structure of porous silicon with simulated one and important results are presented.