摘要
太阳能作为一种绿色可持续的清洁能源,可以转化为热能或电能,是传统能源最重要的替代品。多晶硅太阳能电池由于具有较低的成本而被广泛用于光伏发电领域,降低多晶硅片表面反射率是提升多晶硅太阳能电池效率的重要手段之一。本文分析了硅基太阳能绒面微结构的吸光原理,梳理了各类常见制绒方法。在此基础之上,总结了激光制绒的各类加工方法,概括了不同激光加工方法对多晶硅片表面绒面产生的相应效果,其中,激光复合方法制绒的效果普遍优于单一激光制绒。随后从激光加工工艺的角度,分析了激光加工主要参数对绒面微结构形貌的影响:由于不同波长下多晶硅材料的吸收率不同,各加工效果亦不相同;通过调整脉冲激光加工中的重复频率、扫描速度等参数,可影响制绒面凹坑间距进而改变绒面微结构的密度,通过调整功率、单脉冲能量等因素则影响微结构的烧蚀程度或深度;而入射角度、能量分布及脉宽对制绒亦有明显效果。对比发现,各典型绒面微结构的形貌中,V形纹理比U形纹理更能有效地捕捉吸收光线,而二维复合型陷光微结构比单一型陷光微结构吸光性更好。在此基础之上,论述了化学后处理对提升多晶硅片绒面质量的作用体现,表明化学后处理能改善或消除多晶硅片经激光制绒后形成的熔覆层等相关缺陷,经化学后处理后制成的多晶硅太阳能电池效率显著提高。文章最后对太阳能电池多晶硅表面激光制绒技术进行了总结与展望。
Solar energy is one of the most important substitutes for traditional fossil energy source due to its cleanness and sustainability,which can be absorbed and transferred into heat,and more importantly as electricity when converted via solar cell technology.Polycrystalline silicon solar cells are a widely adopted solar cell technology in the field of photovoltaic power generation.It is of great importance to overcome the problem faced by the solar cells,which is to reduce the incident light reflectivity of the solar cell panel surface in order to enhance the efficiency of the solar cells.In this paper,the light trapping principle is initially introduced,followed by the classifications of the commonly utilized surface texturing processes to reduce the undesired reflectivity.Specifically,laser related texturing methods are reported,as well as the analyses of the corresponding texturing effects on the surface of polycrystalline silicon prepared with different laser texturing methods.It is found that the laser-based hybrid micro-texturing technology overcomes the issues faced by the conventional direct laser texturing process.Furthermore,the effect of laser processing parameters on the surface texturing is analyzed,especially the corresponding light absorptance.Variation of the laser wavelength could affect the silicon surface morphology.Moreover,the tuning of key laser parameters,such as laser repetition rate and laser scanning speed can influence the density of the micro dimples on the surface of the solar cells.The depth of the ablated micro craters can also be tailored by altering the laser power and the pulse energy,as well as modulating the laser incident angle,energy distribution,and pulse duration.Among the typical microtextures,the V-shaped textures are more effective than the U-shaped textures,and 2D light trapping structures prevail over the 1D ones.In addition,the effects of chemical post-processing to enhance the micro structuring are also discussed.The enhancement of the performance of the polycrystalline
作者
成健
廖建飞
杨震
孔维畅
刘顿
CHENG Jian;LIAO Jianfei;YANG Zhen;KONG Weichang;LIU Dun(Center for Sino-UK Ultrafast Laser Processing Research,School of Mechanical Engineering,Hubei University of Technology,Wuhan 430068,China)
出处
《材料导报》
EI
CAS
CSCD
北大核心
2023年第6期12-21,共10页
Materials Reports
基金
中央军委装备预先研究基金项目(6141C25)
湖北省自然科学基金面上项目(2019CFB509)。
关键词
激光制绒
反射率
化学后处理
多晶硅
太阳能电池
laser texturing
reflection
chemical post-processing
polycrystalline silicon
solar cell
