21.3%-efficient n-type silicon solar cell with a full area rear TiOx/LiF/Al electron-selective contact
21.3%-efficient n-type silicon solar cell with a full area rear TiOx/LiF/Al electron-selective contact
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21.3%效率%20n型%20silicon%20solar%20cell%20with%20a%20full%20area%20rear%20TiOx/LiF/Al%20电子选择性%20contact
DOI：
10.1016/j.solmat.2019.110291
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发表时间：
2020
影响因子：
6.9
通讯作者：
Yimao Wan
中科院分区：
文献类型：
--
作者：
Wenjie Wang;Jian He;Di Yan;Chris Samundsett;Sieu Pheng Phang;Zengguang Huang;Wenzhong Shen;James Bullock;Yimao Wan
在这项工作中，我们研究了一种高效的电子选择钝化接触，具有TiOx/LiF/Al接触结构，具有低表面复合和比接触电阻。优化的TiOx层厚度为4 nm，提供了高质量的表面钝化，在5Ωcm n型晶片上实现了3.03ms的少子寿命，饱和电流密度J0为23fA/cm2。此外，在4 nm的TiOx和Al之间插入1 nm的LiF可以将接触电阻率降低到18mΩcm~2。TiOx/LiF/Al接触的低接触电阻率是由于LiF/Al叠层的低功函数导致势垒降低所致。采用TiOx/LiF/Al全面积背面接触的n型单晶硅器件的太阳电池效率达到了21.3%，显示了这种钝化接触在制造高效率硅太阳电池方面的巨大潜力。
In this work, we investigate an efficient electron-selective passivating contact with TiOx/LiF/Al contact structure, which offers both low surface recombination and specific contact resistance. Optimized TiOx layer thickness of 4 nm provides high quality surface passivation, achieving minority carrier lifetime of 3.03 ms on 5 Ω cm n-type wafers, with a saturated current density J0 of 23 fA/cm2. In addition, inserting a 1 nm LiF between the 4 nm TiOx and Al reduces the contact resistivity to 18 mΩ cm2. The low contact resistivity of TiOx/LiF/Al contact is attributed to barrier reduction from the low work function of LiF/Al stack. A champion solar cell efficiency of 21.3% has been achieved for an n-type crystalline silicon device with a full-area rear TiOx/LiF/Al contact, demonstrating the excellent potential of this passivating contact for fabricating high-efficiency silicon solar cells.