Advanced Light scattering through various textured glass surface morphologies in thin film silicon solar cells

It has been a hot debate in recent time whether periodic or random TCO surface morphology showed better light scattering in silicon thin film solar cells (TFSCs). We report an advanced light scattering scheme by various textured glass surface morphologies with high transmittance, haze ratio in visible as well as in near infra-red (NIR) wavelength region for the applications of silicon TFSCs. Three different textured (trapezoid, pyramid and random) glass surface morphologies with high transmittance, rms roughness and haze ratios were selected. The textured glass surface morphologies showed higher optical transmittance (91.77 to 93.04%) as compared to bare glass transmittance (90.94%) in the visible wavelength region. It was observed that the haze ratio was reliant on the surface feature size, etching depth, spacing and rms roughness of glass surfaces. Multi-textured AZO films deposited on micro textured glass surfaces showed higher transmittance 83.78% and haze ratio of 65.06% in the visible wavelength region. The X-ray photoelectron spectroscopic analysis was performed in order to investigate changes in the composition of textured glass surfaces. Amorphous silicon (a-Si) TFSCs were fabricated on periodic and random textured glass surface morphologies showed higher current density (16.55 and 16.68 mA/cm
²
) and efficiency (9.61 and 9.79%), respectively. Due to higher transmittance, haze ratio, high rms roughness and better step coverage, we propose these textured glass surface morphologies for high efficiency amorphous and microcrystalline based silicon thin film solar cells.