钼背电极和掺杂吸收层的制备及其CIGS太阳电池性能研究

发布时间：2018-03-12 10:16

本文选题：CIGS薄膜太阳电池　切入点：底层Mo薄膜　出处：《安徽工程大学》2017年硕士论文　论文类型：学位论文

【摘要】：铜铟镓硒(Cu(In,Ga)Se2,CIGS)薄膜太阳电池具有光电转换效率高、弱光性好、禁带宽度可调等优点,备受光伏界的关注。该电池由Mo背接触电极、CIGS光吸收层、CdS缓冲层、ZnO/ZnO:Al窗口层、金属前栅线电极和MgF2减反层等多层功能材料构成。电池器件的光电转换效率、稳定性等性能,直接受每层薄膜质量的影响。本论文对部分薄膜层进行优化,以期得到高效稳定的CIGS薄膜太阳电池。主要开展了以下几个方面的研究:(1)研究了溅射底层Mo薄膜的工作气压以及底层Mo薄膜的膜厚对Mo薄膜及其CIGS薄膜太阳电性能的影响。结果显示,高溅射气压(7.9 Pa)制备的Mo薄膜具有较高的电阻率和较低的反射率。低溅射气压(1.2 Pa)和较厚的膜厚(531.7 nm)有助于获得较致密、结晶性好的Mo薄膜。在1.2 Pa的工作气压下制备的Mo电极应用于CIGS薄膜太阳电池上获得14.4%的转换效率。(2)研究在钠钙玻璃(SLG)和聚酰亚胺(PI)衬底上采用低衬底温度制备CIGS薄膜并研究其相应的太阳电池性能。结果表明,随着衬底温度的降低,CIGS薄膜材料的XRD衍射图谱中(112)、(220)/(204)和(116)/(312)均呈现出"双峰劈裂"现象。PI衬底和SLG衬底上制备的CIGS薄膜皆出现分层结构,薄膜表层及底层呈现出小尺寸晶粒层,而中间层则为大尺寸晶粒。在器件方面,两种衬底上的CIGS薄膜太阳电池表现出相近的光电转换效率,PI衬底上制备的CIGS薄膜太阳电池具有较低的Voc和FF,但Jsc较高。制备的柔性CIGS薄膜太阳电池(PI衬底)最高转换效率为6.4%。(3)CIGS吸收层中掺入微量的碱金属元素可以有效改善电池性能。本论文将碱金属钾掺入到不同衬底CIGS吸收层中,研究了 K元素的掺杂对薄膜材料及其电池性能的影响。结果发现,钾元素的掺入并未对薄膜晶粒结构和尺寸产生影响,但提升了有阻挡层的玻璃衬底上电池器件的开路电压,而对PI衬底太阳电池并未起到理想中的效果。这是因为PI衬底上CIGS薄膜质量对掺杂效果具有较大的影响,同时碱金属掺入量和电池的划线工艺同样也影响着电池的性能。
[Abstract]:CIGS thin film solar cells have many advantages, such as high photoelectric conversion efficiency, good weak light, adjustable band gap and so on, which have attracted much attention in photovoltaic field. This cell is composed of CIGS buffer layer and ZnO / ZnO: al window layer, which is composed of Mo back contact electrode and CIGS optical absorption layer. The multilayer functional materials such as metal front gate electrode and MgF2 antireflection layer are constructed. The photoelectric conversion efficiency and stability of the battery device are directly affected by the quality of each layer. In this paper, some thin film layers are optimized. In order to obtain CIGS thin film solar cells with high efficiency and stability, the following aspects have been studied: 1) the working pressure of Mo thin films deposited on the substrate and the solar electrical properties of Mo thin films and CIGS thin films on the substrate thickness of Mo thin films have been studied. The effect of energy. The results show that, Mo thin films prepared at high sputtering pressure (7.9 Pa) have higher resistivity and lower reflectivity. Low sputtering pressure (1.2 Pa) and thicker film thickness (531.7 nm) contribute to the compactness of Mo films. Mo thin Films with good Crystallization. The conversion efficiency of Mo electrode prepared at 1.2Pa working pressure for CIGS thin film solar cells has been obtained by 14.4%) the low substrate temperature was used to prepare the Mo film on sodium calcareous glass (SLG) and polyimide (Pi) substrates. The CIGS thin film and its corresponding solar cell performance are studied. The results show that, With the decrease of substrate temperature, the XRD diffraction patterns of CIGS thin films show "bimodal splitting" phenomenon in the XRD diffraction patterns. Both Pi substrates and SLG substrates have layered structures, and the surface and bottom layers of the films exhibit small grain layers. The middle layer is a large grain. In the case of devices, The CIGS thin film solar cells on two kinds of substrates show similar photoelectric conversion efficiency. The CIGS thin film solar cells prepared on Pi substrates have lower Voc and FFF, but higher Jsc. The prepared flexible CIGS thin film solar cells have the highest Pi substrates. The conversion efficiency is 6. 4%. The incorporation of trace alkali metal elements into the absorption layer of CIGS can effectively improve the performance of the battery. In this paper, potassium alkalinity is doped into the CIGS absorption layer on different substrates. The effect of K doping on the properties of thin films and their batteries was studied. It was found that the addition of potassium had no effect on the crystal structure and size of the films, but increased the open circuit voltage of the cell devices on the glass substrate with a barrier layer. This is because the quality of CIGS film on Pi substrate has a great influence on the doping effect, and the addition of alkali metal and the marking process of the cell also affect the performance of the cell.
【学位授予单位】：安徽工程大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TB383.2;TM914.4

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