Light trapping characteristics of glass substrate with hemisphere pit arrays in thin film Si solar cells

• Published in: Chinese physics B 2015-04, Vol.24 (4), p.16-21
• Main Author: 陈乐 王庆康 王阳培华 黄堃 沈向前
• Format: Article
• Language: English
• Subjects: Arrays; Glass; Hemispheres; Photovoltaic cells; Reflectivity; Silicon substrates; Solar cells; Thin films; 光特性; 凹坑; 半球; 太阳能电池阵列; 玻璃基板; 硅太阳能电池; 薄膜; 表面反射率
• ISSN: 1674-1056; 2058-3834; 1741-4199
• DOI: 10.1088/1674-1056/24/4/040202

In this paper, the light trapping characteristics of glass substrate with hemisphere pit （HP） arrays in thin film Si solar cells are theoretically studied via a numerical approach. It is found that the HP glass substrate has good antireflection properties. Its surface reflectance can be reduced by - 50% compared with planar glass. The HP arrays can make the unabsorbed light return to the absorbing layer of solar cells, and the ratio of second absorption approximately equals 30%. Thus, the glass substrate with the hemisphere pit arrays （HP glass） can effectively reduce the total reflectivity of a solar celt from 20% to 13%. The lip glass can also prolong the optical path length. The numerical results show that the total optical path length of the thin film Si solar cell covered with the HP glass increases from 2ω to 409. These results are basically consistent with the experimental results.