微纳二维多齿光栅提高太阳能电池光电转换性能的研究

发布时间：2018-08-14 18:41

【摘要】：太阳能薄膜电池因其体积小、能耗低、制作工艺相对简单而倍受关注。然而太阳能薄膜电池的半导体材料在带隙边缘的吸收率都不高,尤其是对于间接带隙的硅材料,这极大的影响了薄膜电池的光吸收效率。因此,增强太阳能薄膜电池的吸收效率对薄膜电池光电转换性能提升的有重要意义。鉴于此,论文在国家自然科学基金(11264031),江西省青年科学基金重大项目(20143ACB21011),江西省自然科学基金(20151BAB207054,20114BAB201019),南昌航空大学研究生创新基金及博士启动基金(YC2015042,EA201008232)资助下,主要围绕硅基微纳多齿谐振光栅,探索利用光栅衍射和谐振原理来实现宽带、大角度、全偏振光捕获吸收,以获得光电转换效率的显著提升。论文主要研究内容如下:(1)在太阳能薄膜电池硅有源层上面设计了一种宽带微纳二维多齿光栅陷波器,理论分析表明,此器件在300~1200纳米宽谱范围内的透射效率能保持在95%以上,且入射角度在-40度到+40度范围内反射率能维持在5%以下,从而能获得了所需的总衍射带宽、角度谱和偏振特性。(2)为了使得从上层光栅透射进入太阳能薄膜电池的光能被有效吸收,论文在有源层下底面设计了一种微纳多齿光栅反射镜,该反射镜在400-1200纳米波段范围内,入射角度±35度之后反射率达90%以上,该微纳多齿光栅反射镜能使得透射光再次反射回硅有源层而被吸收。(3)为了能充分发挥上、下层光栅的作用,论文在硅太阳能电池有源层上下表面引入上述二维微纳多齿光栅,探索利用光栅衍射和谐振原理来实现宽带、大角度、全偏振光捕获吸收,以获得光电转换效率的显著提升。分析表明,当上层微纳多齿光栅结构高度为340纳米时,硅有源层平均吸收效率可达81.8%。由此可见,入射阳光在顶部和底部二维微纳多齿光栅的共同作用下,与太阳能电池硅吸收层相互作用的光程可大大增加,从而能有效的提高光电转换性能。
[Abstract]:Solar thin-film cells have attracted much attention because of their small size, low energy consumption and relatively simple fabrication process. However, the absorptivity of solar thin film cell semiconductor materials at the edge of the band gap is not high, especially for the indirect band gap silicon material, which greatly affects the optical absorption efficiency of the thin film cell. Therefore, it is important to enhance the absorption efficiency of solar thin film cells for improving their photoelectric conversion performance. In view of this, the thesis is supported by the National Natural Science Foundation of China (11264031), the important Project of Jiangxi Province Youth Science Foundation (20143ACB21011), the Jiangxi Provincial Natural Science Foundation (20151BAB207054n20114BAB201019), the Graduate Innovation Foundation of Nanchang University of Aeronautics and Aviation and the doctoral Start-up Fund (YC2015042EEA201008232). The principle of grating diffraction and resonance is used to realize the acquisition and absorption of wide-band, large-angle and all-polarized light, so as to achieve a remarkable improvement in the photoelectric conversion efficiency. The main contents of this thesis are as follows: (1) A wideband micro-nano two-dimensional multi-tooth grating notch device is designed on the silicon active layer of solar thin film cell. Theoretical analysis shows that the transmission efficiency of the device can be kept above 95% in the wide spectrum range of 300 ~ 1200 nm. The reflectivity of the incident angle can be kept below 5% in the range of -40 degrees to 40 degrees, thus the required total diffraction bandwidth can be obtained. Angle spectrum and polarization characteristics. (2) in order to effectively absorb the light energy transmitted from the upper layer grating to the solar thin film cell, a micro nanodentate grating reflector is designed at the bottom of the active layer. The mirror is in the range of 400-1200 nm. The reflectivity is over 90% after the incident angle of 卤35 degrees. The mirror can make the transmitted light reflect back to the active silicon layer again and be absorbed. (3) in order to give full play to the role of the lower layer grating, In this paper, the two dimensional micro nano multitooth grating is introduced into the upper and lower surface of the active layer of the silicon solar cell, and the principle of grating diffraction and resonance is explored to achieve wide band, large angle, full polarized light capture and absorption, so as to achieve a remarkable improvement of the photoelectric conversion efficiency. The results show that the average absorption efficiency of the silicon active layer can reach 81.8when the structure height of the superstructure is 340 nm. It can be seen that the optical path of the interaction between the incident sunlight and the silicon absorption layer of the solar cell can be greatly increased under the joint action of the top and bottom two-dimensional micro-nano multitooth grating, which can effectively improve the photoelectric conversion performance.
【学位授予单位】：南昌航空大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TM914.4

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