摘要
在合金法提纯太阳能级多晶硅过程中,冷却工艺对初晶硅的形核、生长及杂质分凝具有重要影响。本文探讨了Al-30%Si合金在温度900~600℃的冷却工艺,对比了单一速率冷却和三段式冷却工艺对初晶硅形貌和杂质含量的影响,旨在优化Al-Si合金法提纯工艺。实验结果表明,在单一速率冷却工艺下,1℃/min的冷却速率能显著增大初晶硅晶粒尺寸,降低初晶硅杂质含量,提高杂质去除率。在三段式冷却工艺下,设置的节点温度越靠近高温区域,初晶硅的晶粒尺寸越大,纯度和收率越高;当节点温度为700℃时,可以达到最好的提纯效果,此时初晶硅的尺寸相较于优化前略有减小,但杂质含量与优化前相当,而熔炼时间减少了约62.3%,能耗降低了23.3%。该研究为推进Al-Si合金法提纯太阳能级多晶硅的实用化进程提供了方案并积累了实验数据。
During solvent refining for solar-grade polysilicon,the cooling process significantly influences the nucleation,crystal growth and impurity segregation of primary silicon.This study investigated the cooling process of Al-30%Si alloy over a temperature range of 900℃to 600℃and compared the effects of single-rate cooling and three-stage cooling processes on the morphology and impurity content of primary silicon.The main objective is to optimize the solvent refining process.The results indicate that,under the single-rate cooling process,a cooling rate of 1℃/min can significantly increase the primary silicon grain size,reduce the impurity content in the primary silicon,and improve the impurity removal rate.In contrast,under the three-stage cooling process,a nodal temperature close to the high-temperature region results in a larger grain size and improves the purity and yield of primary silicon.The best purification effect can be achieved when the nodal temperature is set at 700℃.In this case,the grain size of primary silicon is slightly lower,while the impurity content is comparable to that before optimization.At the same time,the optimized process achieves a 62.3%reduction in cooling duration and a 23.3%decrease in energy consumption.This study provides a potential strategy to fabricate solar-grade polysilicon using Al-Si solvent refining,which is of significant experiment accumulation.
作者
唐洪
狄嘉慧
杨平平
李少猛
施玉洁
何占伟
赵紫薇
高忙忙
TANG Hong;DI Jiahui;YANG Pingping;LI Shaomeng;SHI Yujie;HE Zhanwei;ZHAO Ziwei;GAO Mangmang(Ningxia Key Laboratory of Photovoltaic Materials,School of Materials and New Energy,Ningxia University,Yinchuan 750021,China)
出处
《人工晶体学报》
北大核心
2025年第8期1454-1462,共9页
Journal of Synthetic Crystals
基金
国家自然科学基金(52164047)
中国科学院“西部之光”人才培养计划(XAB2022YW10)
宁夏回族自治区重点研发项目(2022CXLHT001)。
关键词
太阳能级多晶硅
Al-Si合金法
冷却速率
节点温度
工艺优化
solar grade polysilicon
solvent refining in Al-Si alloy
cooling rate
nodal temperature
process optimization
