周期性结构Mo背电极的设计及其陷光特性研究与应用

Design of the periodical textured Mo back electrode and its light trapping characteristic and application

为了改善金属钼(Mo)电极的光学特性,采用类桑拿法通过聚苯乙烯小球自组装制备了具有周期性结构的Mo电极,通过控制钼的沉积厚度和小球的刻蚀时间来获得具有不同高度和周期的衬底结构,并研究了其对周期性Mo衬底光学特性的影响。实验结果表明:周期性结构衬底显著提高了长波区域(>1 100nm)的反射,尤其当铜锌锡硒(CZTSe)吸收层厚度减薄至0.5μm时,为了进一步增加光吸收,通过在CZTSe薄膜表面引入金字塔形貌的氧化锌,与周期性衬底形成了光学陷阱结构,增加了CZTSe光吸收。该结果对超薄化合物电池的研究具有一定的指导作用。

To improve the optical property of molybdenum（Mo）electrodes,periodical textured Mo electrodes by self-assembling monolayer and hexagonal closely-arranged polystyrene（PS）spheres using a Sauna-like method were fabricated and modulated in this study.By modulating the thicknesses of Mo electrodes and the etching times of PS spheres,the substrate morphologies with various height and period features were effectively acquired and their effects on optical properties of periodical textured Mo electrodes were simultaneously investigated.Experimental results show that the long-wavelength reflection（1 100nm）can be significantly improved with our proposed periodical textured Mo electrodes,thereby enhancing the light absorption in Copper Zinc Tin Selenium（CZTSe）absorbers,especially in ultrathin ones（0.5μm）.By further introducing metal-organic chemical vapor deposition（MOCVD）prepared pyramid-like zinc oxide（ZnO）films on CZTSe absorbers to form a light trapping architecture with the periodical textured Mo substrates,we successfully improve the light absorption in CZTSe absorbers further.Our proposed periodical textured Mo electrodes and the light trapping architecture may pave the way for the device design of ultrathin solar cells,such as CIGS et al.