title: Approaching conversion limit with all-dielectric solar cell reflectors.
abstract: Metallic back reflectors has been used for thin-film and wafer-based solar cells for very long time. Nonetheless, the metallic mirrors might not be the best choices for photovoltaics. In this work, we show that solar cells with all-dielectric reflectors can surpass the best-configured metal-backed devices. Theoretical and experimental results all show that superior large-angle light scattering capability can be achieved by the diffuse medium reflectors, and the solar cell J-V enhancement is higher for solar cells using all-dielectric reflectors. Specifically, the measured diffused scattering efficiency (D.S.E.) of a diffuse medium reflector is >0.8 for the light trapping spectral range (600nm-1000nm), and the measured reflectance of a diffuse medium can be as high as silver if the geometry of embedded titanium oxide(TiO(2)) nanoparticles is optimized. Moreover, the diffuse medium reflectors have the additional advantage of room-temperature processing, low cost, and very high throughput. We believe that using all-dielectric solar cell reflectors is a way to approach the thermodynamic conversion limit by completely excluding metallic dissipation.
authors.forename: Sze Ming
authors.initials: SM
authors.lastname: Fu
authors.forename: Yi-Chun
authors.initials: YC
authors.lastname: Lai
authors.forename: Chi Wei
authors.initials: CW
authors.lastname: Tseng
authors.forename: Sheng Lun
authors.initials: SL
authors.lastname: Yan
authors.forename: Yan Kai
authors.initials: YK
authors.lastname: Zhong
authors.forename: Chang-Hong
authors.initials: CH
authors.lastname: Shen
authors.forename: Jia-Min
authors.initials: JM
authors.lastname: Shieh
authors.forename: Yu-Ren
authors.initials: YR
authors.lastname: Li
authors.forename: Huang-Chung
authors.initials: HC
authors.lastname: Cheng
authors.forename: Gou-chung
authors.initials: GC
authors.lastname: Chi
authors.forename: Peichen
authors.initials: P
authors.lastname: Yu
authors.forename: Albert
authors.initials: A
authors.lastname: Lin