InGaAsP/InGaAs双结太阳电池的开路电压损耗抑制  

Reducing Voc loss in InGaAsP/InGaAs dual-junction solar cells

作　　者：陆宏波 李欣益[2] 李戈[2] 张玮 胡淑红[1] 戴宁[1] 杨瑰婷[2] LU Hong-Bo;LI Xin-Yi;LI Ge;ZHANG Wei;HU Shu-Hong;DAI Ning;YANG Gui-Ting(State Key Laboratory of Infrared Physics,Shanghai Institute of Technology Physics of the Chinese Academy of Sciences,Shanghai 200083,China;State Key Laboratory of Space Power-sources,Shanghai Institute of Space Power-sources,Shanghai 200245,China;University of Chinese Academy of Sciences,Beijing 100049,China)

机构地区：[1]中国科学院上海技术物理研究所,红外物理国家重点实验室,上海200083 [2]上海空间电源研究所,空间电源技术国家重点实验室,上海200245 [3]中国科学院大学,北京100049

出　　处：《红外与毫米波学报》2021年第1期7-11,共5页Journal of Infrared and Millimeter Waves

基　　金：the National Nature Science Foundation of China(61474076 and 61704106);the Young Elite Scientist Sponsorship Program by China Association for Science and Technology(2017QNRC001);Shanghai Rising-Star Program(18QB1402500 and 19QB1403800).

摘　　要：现有1.0 eV/0.75 eV InGaAsP/InGaAs双结太阳电池的开路电压小于各子电池的开路电压之和,鲜有研究探索开路电压损耗的来源以及如何抑制。通过研究发现,InGaAs底电池背场/基区界面处的少数载流子输运的主要机制是热离子发射,而不是缺陷诱导复合。SIMS测试表明,采用InP或InAlAs背场均不能有效抑制Zn掺杂剂的扩散。此外,由于生长过程中持续的高温热处理,Ⅲ-Ⅴ族主元素在界面处发生了热扩散。为了抑制上述现象,提出了一种新型InP/InAlAs超晶格背场,并应用到InGaAs底电池中。制备得到的双结太阳电池在维持短路电流密度不变的情况下,开路电压提升到997.5 mV,与传统采用InP背场的双结太阳电池相比,开路电压损耗降低了30 mV。该研究成果对提升四结太阳电池的整体开路电压有重要意义。Smaller Voc of 1. 0 eV/0. 75 eV InGaAsP/InGaAs double-junction solar cell(DJSC)than the Vocsum of individual subcells has been observed,and there is little information of the origin of such Vocloss and how to minimize it. In this paper,it is disclosed that the dominant mechanism of minority-carrier transport at back-surfacefield(BSF)/base interface of the bottom subcell is thermionic emission,instead of defect-induced recombination,which is in contrast to previous reports. It also shows that both InP and InAlAs cannot prevent the zinc diffusion effectively. In addition,intermixing of major Ⅲ-Ⅴ element occurs as a result of increasing thermal treatment. To suppress the above negative effects,an initial novel InP/InAlAs superlattice(SL)BSF layer is then proposed and employed in bottom InGaAs subcell. The Vocof fabricated cells reach 997. 5 mV,and a reduction of 30 mV in Voc loss without lost of Jsc,compared with the results of conventional InP BSF configuration,is achieved. It would benefit the overall Vocfor further four-junction solar cells.

关 键 词：背场 InGaAsP/InGaAs双结电池 开路电压 超晶格 

分 类 号：TM914.4[电气工程—电力电子与电力传动]