Scattering properties of ZnO gratings on Al back reflectors for thin f ilm silicon solar cells
Light scattering properties of back grating structures that composed of one-dimensional ZnO gratings and a flat 300-nm Al reflectors are investigated. Results show that grating structures cause an 8% reduction of the total reflectivity, as grating periods increasing from 620 to 1 435 nm, both the diffuse reflectivity and the haze parameter enhance drastically between 400 and 1 000 nm, whereas the diffraction angle at normal incidence reduce greatly, which agree with the values calculated from grating equation. It is concluded that rear gratings have the potential of scattering a substantial amount of incident light to specific angles and enlarging the optical path.
备注：This work was supported by the National Natural Science Foundation of China (No. 60977028) and the Key Project Foundation of Shanghai (No. 09JC1413800).
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Renchen Liu, Yonggang Wu, Guangde Tong, Zihuan Xia, "Scattering properties of ZnO gratings on Al back reflectors for thin f ilm silicon solar cells," Chinese Optics Letters 11(s1), S10504 (2013)