Abstract:
Silicon, being an indirect band gap material, has low optical absorption coefficient especially
at the energies near the band gap. Hence, the efficient light management scheme is needed to
trap the light inside the active region of the solar cell until it get absorbed. Silicon
nanostructures, with feature size and periodicity in the order of the wavelength of light, exhibit
excellent anti-reflection and light trapping properties for broad wavelengths and incident
angles [1]. These nanostructures significantly enhance the light absorption by multiple internal
reflection and also reduce the front surface light reflection by gradually increases the refractive
index from air to substrate. The reflectivity of these structures mainly depends on the
periodicity, height, duty cycle, and shape of the nanostructures [2]. In this work, the optical
simulation for the reflectivity of dome-like hemispherical silicon nanostructure was carried
out using Lumerical FDTD commercial software. The minimum reflectivity of the optimized
hemisphere structure was 0.8% whereas the reflectivity of 39% for planner silicon at 460 nm
wavelength.
