An Effective Way to Simultaneous Realization of Excellent Optical and Electrical Performance in Large-scale Si Na-no/micro-structures
Despite the optical advantage of near-zero reflection, the silicon nanowire arrays (SiNWs) based solar cells cannot yet achieve satisfactory high efficiency due to the serious surface recombination arising from the greatly enlarged surface area.The trade-off between reflection and recombination fundamentally prevents the conventional SiNWs structure from having both minimal optical and electrical losses.Here we report the simultaneous realization of the best optical anti-reflection (the solar averaged reflectance of 1.38%) and electrical passivation (the surface recombination velocity of 44.72 cm/s) by effectively combining the Si nano/micro-structures (N/M-Strus) with ALD-Al2O3-passivation.The composite structures are pre-pared on the pyramid-textured Si wafers with large-scale 125 × 125 mm2 by the two-step metal-assisted chemical etch-ing method and the thermal atomic-layer-deposition (ALD)-Al2O3 treatment.While the excellent optical an-ti-reflection is observed due to the complementary contribution of Si N/M-Strus at short wavelength and ALD-Al2O3 at long wavelength, the low recombination has also been realized since the field effect passivation is enhanced for the longer-and-thinner SiNWs through the more effective suppression of the minority carrier movement and the reduction of the pure-pyramid-textured surface recombination.We have further numerically modeled the Al2O3-passivated Si N/M-Strus based solar cell and obtain the high conversion efficiency of 21.04%.The present work opens a new way to realize high efficiency SiNWs based solar cells.
silicon nanowires large-scale atomic layer deposition Al2O3 field effect passivation minority carrier lifetime
Zengguang Huang Sihua Zhong Xia Hua Xingxing Lin Xiangyang Kong Ning Dai Wenzhong Shen
Laboratory of Condensed Matter Spectroscopy and Opto-Electronic Physics,and Key Laboratory of Artifi Laboratory of Condensed Matter Spectroscopy and Opto-Electronic Physics,and Key Laboratory of Artifi School of Materials Science and Engineering,Shanghai Jiao Tong University,Shanghai 200240,People”s R National Laboratory for Infrared Physics,Shanghai Institute of Technical Physics,Chinese Academy of
国内会议
广州
英文
1-11
2015-05-01（万方平台首次上网日期，不代表论文的发表时间）