Simulation of optical properties of silicon solar cells textured with penetrating V-shaped grooves

The coefficients of reflection (R), transmission (T), and absorption (A) of light for two wavelengths λ = 1000 and 1100 nm for silicon wafers that have thicknesses t = 50, 100, and 200 μm and are textured with penetrating V-shaped grooves with various geometries have been calculated; the half-width of groove’s base w (10, 20, and 30 μm) and the depth of the groove d (0 ≤ d ≤ t) have been varied. In the case of an increase in the aspect ratio d/w (in the case of λ = 1100 nm), the absorption curve A(d/w) monotonically ascends from 6.6 to 67.6%, whereas, for λ = 1000 nm, a nontrivial dependence A(d/w) is observed: the absorption coefficient first increases to 54%, attains then a maximum of 97% at d/w = 3, and then decreases at d > t/2 for all values of w. This effect of a decrease in absorption with an increase in d/w distinguishes texturing with penetrating grooves from conventional surface texturing. Distributions of angles of deviations of photons in the plane of bottoms of grooves are obtained; these distributions are represented by a set of δ-type functions.