title: Enhanced broadband and omnidirectional performance of Cu(In,Ga)Se2 solar cells with ZnO functional nanotree arrays.
abstract: An effective approach is demonstrated for enhancing photoelectric conversion of Cu(In,Ga)Se2 (CIGS) solar cells with three-dimensional ZnO nanotree arrays. Under a simulated one-sun condition, cells with ZnO nanotree arrays enhance the short-circuit current density by 10.62%. The omnidirectional anti-reflection of CIGS solar cells with various ZnO nanostructures is also investigated. The solar-spectrum weighted reflectance is approximately less than 5% for incident angles of up to 60° and for the wavelengths primarily from 400 nm to 1000 nm. This enhancement in light harvesting is attributable to the gradual refractive index profile between the ZnO nanostructures and air.
authors.affiliation: Department of Electronic Engineering, Chang Gung University, 259 Wen-Hwa 1st Road, Kwei-Shan, Taoyuan 333, Taiwan.
authors.forename: Ming-Yang
authors.initials: MY
authors.lastname: Hsieh
authors.forename: Shou-Yi
authors.initials: SY
authors.lastname: Kuo
authors.forename: Hau-Vei
authors.initials: HV
authors.lastname: Han
authors.forename: Jui-Fu
authors.initials: JF
authors.lastname: Yang
authors.forename: Yu-Kuang
authors.initials: YK
authors.lastname: Liao
authors.forename: Fang-I
authors.initials: FI
authors.lastname: Lai
authors.forename: Hao-Chung
authors.initials: HC
authors.lastname: Kuo