title: Efficiency improvement of InGaP/GaAs/Ge solar cells by hydrothermal-deposited ZnO nanotube structure.
abstract: In this paper, a zinc oxide (ZnO) nanotube, fabricated by the hydrothermal growth method on triple-junction (T-J) solar cell devices to enhance efficiency, is investigated. Compared to those of bare T-J solar cells (without antireflection (AR) coating) and solar cells with Si3N4 AR coatings, the experimental results show that the T-J solar cells, which use a ZnO nanotube as an AR coating, have the lowest reflectance in the short wavelength spectrum. The ZnO nanotube has the lowest light reflection among all experimental samples, especially in the range of 350 to 500 nm from ultraviolet (UV) to visible light. It was found that a ZnO nanotube can enhance the conversion efficiency by 4.9%, compared with a conventional T-J solar cell. The Si3N4 AR coatings also enhance the conversion efficiency by 3.2%.The results show that a cell with ZnO nanotube coating could greatly improve solar cell performances.
authors.affiliation: Department of Materials Science and Engineering, National Chiao Tung University, 1001 University Road, Hsinchu 300, Taiwan.
authors.forename: Chen-Chen
authors.initials: CC
authors.lastname: Chung
authors.affiliation: Department of Materials Science and Engineering, National Chiao Tung University, 1001 University Road, Hsinchu 300, Taiwan.
authors.forename: Binh Tinh
authors.initials: BT
authors.lastname: Tran
authors.affiliation: Industrial Technology Research Institute, Mechanical and Systems Research Labs, 195, Sec. 4, Chung Hsing Road, Chutung, Hsinchu 31040, Taiwan.
authors.forename: Kung-Liang
authors.initials: KL
authors.lastname: Lin
authors.affiliation: Department of Materials Science and Engineering, National Chiao Tung University, 1001 University Road, Hsinchu 300, Taiwan.
authors.forename: Yen-Teng
authors.initials: YT
authors.lastname: Ho
authors.affiliation: Department of Materials Science and Engineering, National Chiao Tung University, 1001 University Road, Hsinchu 300, Taiwan.
authors.forename: Hung-Wei
authors.initials: HW
authors.lastname: Yu
authors.affiliation: Department of Materials Science and Engineering, National Chiao Tung University, 1001 University Road, Hsinchu 300, Taiwan.
authors.forename: Nguyen-Hong
authors.initials: NH
authors.lastname: Quan
authors.affiliation: Department of Materials Science and Engineering, National Chiao Tung University, 1001 University Road, Hsinchu 300, Taiwan.
authors.forename: Edward Yi
authors.initials: EY
authors.lastname: Chang
keywords: Hydrothermal; Triple-junction; ZnO nanotube