单靶磁控溅射Cu(In,Ga)Se_(2)太阳电池的背接触界面设计  

Design of back-contact interface of Cu(In,Ga)Se_(2)solar cells by single-target magnetron sputtering

作　　者：田杉杉 高倩 高泽冉 熊雨晨 丛日东 于威 Tian Shan-Shan;Gao Qian;Gao Ze-Ran;Xiong Yu-Chen;Cong Ri-Dong;Yu Wei(National&Local Joint Engineering Laboratory of New Energy Optoelectronic Devices,College of Physics Science&Technology,Hebei University,Baoding 071002,China)

机构地区：[1]河北大学物理科学与技术学院,新能源光电器件国家地方联合工程实验室,保定071002

出　　处：《物理学报》2024年第17期294-304,共11页Acta Physica Sinica

摘　　要：通过磁控溅射单一四元靶材磁控得到的黄铜矿Cu(In,Ga)Se_(2)(CIGS)太阳电池开发的主要瓶颈是严重的载流子复合,其开路电压非常低.CIGS与钼(Mo)之间不良的缺陷环境是吸收体和界面复合严重的主要原因之一.其中,在背界面处引入的CuGaSe_(2)(CGS)低温缓冲层可以有效地抑制吸收体与背电极在高温磁控过程中的不利界面反应,从而获得高质量的晶体.通过这种背界面工程,不仅可以很好地解决吸收体和界面质量不佳的问题,而且有利于在吸收层中形成梯度带隙结构,从而使深能级InGa缺陷转换为较低能级的VCu缺陷,最终CIGS太阳电池的转换效率达到15.04%.这项工作为直接溅射高效率CIGS太阳电池的产业化提供了一种新的方法.Thin-film solar cells provide an opportunity to reduce the cost of converting solar energy into electricity by replacing expensive and thick silicon wafers,which account for more than 50%of the total cost of photovoltaic(PV)modules.However,many thin-film solar cell materials result in low PV performance due to enhanced recombination through defect states.Cu(In,Ga)Se_(2)(CIGS)is a promising thin-film solar cell material due to its direct tunable bandgap,high absorption coefficient,low effective electron and hole mass,and abundant constituent elements.Among them,magnetron sputtering or selenization technology is widely used to catch up with the development of preparing large-area CIGS thin-film solar cells because of its uniform film composition and simple process.However,the use of toxic gases such as H2Se and H2S and the difficulty in forming gradient bandgaps limit their development.In this work,the“V”Ga gradient classification of the absorbing layer of CIGS solar cells is realized by sputtering CuGaSe_(2)(CGS)thin layers of different thickness values in the room temperature layer by sputtering and selenium-free methods of quaternary target sputtering.Firstly,the microstructure of the film is characterized by scanning electron microscope,X-ray diffraction,Raman and X-ray photoelectron spectroscopy,and when the CGS layer is located in the middle of the low-temperature layer,the grain size of the film is the largest,the crystallinity is the best,forming a“V-shaped”structure of CGI on the back of the absorbing layer.Subsequently,IV and external quantum efficiency(EQE)tests show that the optimized cell efficiency is as high as 15.04%,and the light response intensity is enhanced in the 300-1200 nm band.Finally,the admittance spectrum(AS)test shows that the defect energy level of the solar cell changes from InGa defect to VCu defect of lower energy level,and the defect density decreases from 7.04×10^(15) cm^(-3) to 5.51×10^(15) cm^(-3).This is comparable to the recording efficiency of the current single-targ

关 键 词：Cu(In Ga)Se_(2) 太阳电池 磁控溅射 V 型带隙 缺陷特性 

分 类 号：TM914.4[电气工程—电力电子与电力传动]