title: Pore size dependence of diffuse light scattering from anodized aluminum solar cell backside reflectors.
abstract: The development of backside reflectors (BSRs) is crucial for the efficiency of future low cost thin-film silicon solar cells. In this work, the scattering efficiency of bare aluminum BSRs with different pore sizes and ordering of surface microstructures are investigated. The BSRs were fabricated by utilizing the process of self-ordering anodic oxidation on aluminum foils resulting in regions with an approximately hexagonally periodic surface microstructure. It was found that the total and diffuse light scattering reflectance spectra showed opposite tendencies when increasing the pore size of the microstructures. When the pore size was increased to 700 nm, more than 68% of the incident light with wavelengths from 250 nm to 800 nm was reflected by scattering. For a similar geometry, except that it had less ordering, this number was increased to around 80%. This large fraction of reflected light observed in the form of scattering is promising for the use of the considered geometries as BSRs in thin-film silicon solar cells.
authors: Department of Physics and Nanotechnology, Aalborg University, Skjernvej 4A, 9220 Aalborg East, Denmark.
authors: Yao-Chung
authors: YC
authors: Tsao
authors: Thomas
authors: T
authors: Søndergaard
authors: Esben
authors: E
authors: Skovsen
authors: Leonid
authors: L
authors: Gurevich
authors: Kjeld
authors: K
authors: Pedersen
authors: Thomas Garm
authors: TG
authors: Pedersen
mesh_terms: D000535:Aluminum / Q000737:chemistry*; D011211:Electric Power Supplies; D004867:Equipment Design; D008027:Light; D049329:Nanostructures / Q000737:chemistry; D036103:Nanotechnology / Q000379:methods*; D012031:Refractometry / Q000379:methods*; D012542:Scattering, Radiation; D012825:Silicon / Q000737:chemistry*; D012993:Solar Energy
chemical_list: D000535:Aluminum; D012825:Silicon