氧化随机织构硅表面对单晶硅太阳电池性能的影响研究  

The effect of oxidation randomly textured up-pyramid on the silicon solar cell

作　　者：周春兰[1] 励旭东[2] 王文静[1] 赵雷[1] 李海玲[1] 刁宏伟[1] 曹晓宁[1] 

机构地区：[1]中国科学院电工研究所,中国科学院太阳能热利用及光伏系统重点实验室,北京100190 [2]北京市太阳能研究所有限公司,北京100083

出　　处：《物理学报》2011年第3期767-773,共7页Acta Physica Sinica

基　　金：国家高技术研究发展计划(批准号:2007AA05Z437);中国科学院知识创新工程重要方向项目(批准号:KGCX2-YW-382)资助的课题~~

摘　　要：热氧化生长的SiO2薄膜经常在高效单晶硅太阳电池中被用作扩散掩膜,化学镀掩膜,钝化层或者基本的减反射层.在这些高效太阳电池中,经常使用碱性溶液对单晶硅表面进行处理,得到随机分布的正金字塔结构的织绒表面,减少表面的光反射.表面氧化后的正金字塔太阳电池暗反向电流-电压呈现"软击穿"现象,并联电阻明显下降.研究结果表明引起这些现象的原因在于氧化正金字塔表面会导致在体内形成位错型缺陷,这些缺陷能够贯穿整个pn结,导致太阳电池的并联电阻下降,同时载流子在位错型缺陷在能隙中引入的能级处发生复合,导致空间电荷区复合电流增加.通过酸性溶液对织绒表面进行化学腐蚀之后能够减少缺陷的形成.Thermally grown silicon dioxide is commonly used in high-efficiency monocrystalline silicon solar cell designs as a diffusion mask,electroless plating mask,passivation layer and rudimentary anti-reflection coating. These high efficiency device designs also utilize upright random textured up-pyramids etched by alkalinous solution to minimize front surface reflection. The silicon solar cells passivated with thermal SiO2 /plasma SiN stacks have the evident character： the dark reverse current-voltage curve presents＂soft breakdown＂,and the shunt resistance is lower than that of silicon solar cells passivated with the plasma SiN. The study shows that the cause of monocrystalline silicon solar cell performance degradation is the dislocation induced by the thermal growth of silicon dioxide on textured wafers. The performance of thermal SiO2 /plasma SiN stack passivated silicon solar cells has evident improvement when a 2-min isotropic etching was applied after surface texturing to round off the pyramids.

关 键 词：热氧化 随机织构 位错 太阳电池 

分 类 号：TM914.4[电气工程—电力电子与电力传动]