p型TOPCon结构的隧穿氧化和钝化工艺研究

doi:10.16553/j.cnki.issn1000-985x.20241029.003

摘要/Abstract

摘要： 为深入研究p型TOPCon结构的制备工艺和钝化性能,本文通过实验研究了隧穿氧化层生长过程中氧气流量、氧化温度和氧化时间对氧化层质量的影响,以及在不同硼扩散温度下p-poly的钝化性能和方块电阻。实验结果表明,氧气流量达到15 slm(标准升每分钟)以上,p-poly的隐开路电压平均值达到730 mV,暗饱和电流密度低至3.5 fA/cm²。氧化温度和时间分别达到620 ℃和30 min时,p-poly的隐开路电压可提升至735 mV;随着氧化温度的提高或者氧化时间的延长,p-poly的隐开路电压趋于稳定。硼扩散温度为960 ℃时,p-poly的方块电阻保持在132 Ω/□,硅基体中的掺杂结深为0.25 μm,获得了良好的钝化性能。本文所确定的工艺参数可制备出具有良好钝化性能的p-poly结构,对未来p型TOPCon结构在高效晶硅电池上的产业化应用提供了一定的数据支撑。

关键词: p型TOPCon结构, 低压化学气相沉积, 钝化质量, 隐开路电压, 暗饱和电流密度, 太阳能电池

Abstract: In order to further investigate the preparation process and passivation performance of p-type TOPCon structure, experimental investigations were conducted on the effects of oxygen flow rate, oxidation temperature, and oxidation time on the quality of oxide layer during the growth of tunnel oxide layer. Additionally, the passivation performance and sheet resistance of p-poly at different boron diffusion temperatures were also examined. The experimental results demonstrate that increasing the oxygen flow rate to 15 slm (standard liter per minute) leads to an average hidden open circuit voltage of 730 mV, and a dark saturation current density as low as 3.5 fA/cm² for p-poly. Furthermore, when oxidation temperature is 620 ℃ and oxidation time reaches 30 min, the imply open circuit voltage increases to 735 mV. It is observed that both increasing oxidation temperature and extending oxidation time tend to stabilize the imply open circuit voltage. Moreover, when maintaining a boron diffusion temperature at 960 ℃, a sheet resistance value of p-poly remains at 132 Ω/□ while achieving a dopant junction depth of 0.25 μm in silicon. This configuration exhibits excellent passivation performance. The determined process parameters in this study enable the preparation of p-poly structures with superior passivation performance and provide valuable data support for future industrial applications involving P-type TOPCon structures in high-efficiency crystalline silicon cells.

Key words: p-type TOPCon structure, low pressure chemical vapor deposition, passivation quality, imply open circuit voltage, dark saturation current density, solar cell

中图分类号:

TM914.4

高嘉庆, 屈小勇, 吴翔, 郭永刚, 王永冈, 汪梁, 谭新, 杨鑫泽. p型TOPCon结构的隧穿氧化和钝化工艺研究[J]. 人工晶体学报, 2025, 54(1): 133-138.

GAO Jiaqing, QU Xiaoyong, WU Xiang, GUO Yonggang, WANG Yonggang, WANG Liang, TAN Xin, YANG Xinze. Tunneling Oxidation and Passivation Process of p-Type TOPCon Structure[J]. Journal of Synthetic Crystals, 2025, 54(1): 133-138.

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