Novel etching method on high rate ZnO:Al thin films reactively sputtered from dual tube metallic targets for silicon-based solar cells
Novel etching method on high rate ZnO:Al thin films reactively sputtered from dual tube metallic targets for silicon-based solar cells
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DOI：
10.1016/j.solmat.2010.11.033
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发表时间：
2011-03
影响因子：
6.9
通讯作者：
H. Zhu;J. Hüpkes;E. Bunte;J. Owen;Sumei Huang
中科院分区：
文献类型：
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作者：
H. Zhu;J. Hüpkes;E. Bunte;J. Owen;Sumei Huang
以高达90nmm/min的速度从金属靶上反应溅射制备了高透明导电的掺铝氧化锌薄膜（ZnO:Al）。为了在硅薄膜太阳能电池中作为透明光散射前触点的应用，采用了纹理刻蚀工艺。通常，很难在盐酸中实现适当的蚀刻特征，因为沉积过程必须调整，而且相互关系还没有得到很好的理解。因此，我们提出了一种新的基于氢氟酸的两步蚀刻方法。通过调整蚀刻参数，我们改变了表面形貌，获得了直径为1-2μm、深度约250nm的大型陨石坑的规则分布。采用优化后的ZnO:Al薄膜作为光散射透明前接触，制备了微晶硅单结太阳电池（μc-Si:H）和非晶/微晶硅（a-Si:H/μc-Si:H）串联太阳电池，效率分别高达8.2%和11.4%。
Highly transparent and conductive aluminum-doped zinc oxide thin films (ZnO:Al) were reactively sputtered from metallic targets at high rate of up to 90nmm/min. For the application as transparent light scattering front contact in silicon thin film solar cells, a texture etching process is applied. Typically, it is difficult to achieve appropriate etch features in hydrochloric acid as the deposition process must be tuned and the interrelation is not well understood. We thus introduce a novel two-step etching method based on hydrofluoric acid. By tuning the etch parameters we varied the surface morphology and achieved a regular distribution of large craters with the feature size of 1–2μm in diameter and about 250nm in depth. Microcrystalline silicon single junction solar cells (μc-Si:H) and amorphous/microcrystalline silicon (a-Si:H/μc-Si:H) tandem solar cells with high efficiency of up to 8.2% and 11.4%, respectively, were achieved with optimized ZnO:Al films as light scattering transparent front contact.