| RESEARCH PAPER |
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| Influence of SiO2 Nanosphere on the Performance of p+ Layer Formed by B Diffusion from Boric Acid Solution |
| YANG Nannan, SHEN Honglie, JIANG Ye, JIN Lei, LI Jinze, WU Wenwen, YU Shuanglong, YANG Yan
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| Jiangsu Key Laboratory of Materials and Technology for Energy Conversion, College of Materials Science and Technology, Nanjing University of Aeronautics and Astronautics, Nanjing 210016 |
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Abstract In order to improve the quality of B doped layer by diffusion, a novel boron source mixed with SiO2 nanosphere was introduced. Scanning electronic microscopy, four probe method and minority carrier lifetime measurement were adopted to study the influence of SiO2 nanosphere on the performance of p+ layer formed by B diffusion from boric acid solution. It was found that the thickness of boron rich layer (BRL) decreased from 130 nm to 15 nm compared with that produced without addition of SiO2 nanosphere. At the same time, the uniformity of diffusion increased from 88.17% to 96.79%. In addition, junction depth decreased slightly and minority carrier lifetime in the samples increased apparently after using mixed boric acid solution with SiO2 nanosphere. All the results above indicated that SiO2 nanosphere could evidently enhance the property of the p+ layer formed by liquid B source diffusion from boric acid solution.
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Published: 08 May 2018
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2017, Vol. 31 
