Modulated surface textured glass as substrate for high efficiency microcrystalline silicon solar cells

• Published in: Solar energy materials and solar cells 2015-02, Vol.133, p.156-162
• Main Authors: Yang, Guangtao, van Swaaij, René A.C.M.M., Tan, Hairen, Isabella, Olindo, Zeman, Miro
• Format: Article
• Language: English
• Subjects: Density; Deposition; Glass; Glass texturing; Light trapping; Modulated surface textures; Photovoltaic cells; Silicon substrates; Solar cells; Surface layer; Texture; Thin-film silicon solar cells; Volatile organic compounds
• ISSN: 0927-0248; 1879-3398
• DOI: 10.1016/j.solmat.2014.11.013

In this paper, we investigate three different procedures for making modulated surface textures (MST) on glass substrates and show the application of these substrates to microcrystalline silicon solar cells. MST substrates have broader surface angle distribution (AD) than a single textured glass substrate and this distribution peaks at higher angles. Therefore, (i) the haze in reflection of MST substrates covered with an Ag layer is over 99% in the wavelength range above 350nm, which is higher than in the case of a single textured glass substrate; (ii) more reflected light is scattered into higher angles, resulting in a broader reflective angular intensity distribution (AID) in air. These properties lead to a higher Jsc for n-i-p microcrystalline silicon solar cells deposited on the MST substrates compared to cells deposited on single textured glass substrate. A solar cell deposited on a MST glass substrate with smoother peaks shows the highest electrical performance (Voc×FF value), because of a lower density of defective regions. The best cell achieved in this work has an active-area efficiency of 10.49%, with a Voc of 0.532V, a Jsc of 26.36mA/cm2, and a FF of 74.8% for a 3-μm thick absorber layer. [Display omitted] •Modulated surface textures are prepared by three different approaches.•Modulated surface textures have a high haze value and scatter light into large angles.•Solar cells deposited on modulated surface textures show high short circuit current density.•Solar cells deposited on modulated surface textures with smoothened peaks show a high Voc×FF product and are nearly free of defective regions.•The highest efficiency for n-i-p μc-Si:H single junction solar cell fabricated on modulated surface textures substrate is 10.49%.