温度梯度对多晶硅感应熔炼除杂效果的影响
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摘要
以低硼工业硅为原料,基于真空感应熔炼技术,通过调控界面前沿的温度梯度,比较分析固液前沿温度梯度的变化对多晶硅铸锭定向凝固过程中金属杂质分凝的影响。温度梯度为473.62 K/m时,铸锭出成率达到63%,当温度梯度增大到940.51 K/m时,提纯区比例提高至88%。以Fe、Ni、Cu、Ti为研究元素,分别计算温度梯度增大前后杂质的扩散层厚度和有效分凝系数,结果表明,随着温度梯度的增大,杂质的扩散层厚度和有效分凝系数均减小,可大大提高杂质的分凝去除效果及铸锭的出成率。
The influence of temperature gradient on impurity segregation of metal impurities in polycrystalline silicon during directional solidification is analyzed by regulating the temperature gradient at the front of the solid-liquid boundary interface. When the temperature gradient was 473.62 K/m,the yield of silicon was 63%. When the temperature gradient increased to 940.51 K/m,the proportion of the purification area increased to 88%. The thickness of diffusion layer and effective segregation coefficient of Fe,Ni,Cu and Ti were calculated under different temperature gradient conditions. The results show that the diffusion layer thickness and the effective segregation coefficient of metal impurities decreased with the increase of temperature gradient,which greatly improves the removal of impurity segregation,and improves the yield.
The influence of temperature gradient on impurity segregation of metal impurities in polycrystalline silicon during directional solidification is analyzed by regulating the temperature gradient at the front of the solid-liquid boundary interface. When the temperature gradient was 473.62 K/m,the yield of silicon was 63%. When the temperature gradient increased to 940.51 K/m,the proportion of the purification area increased to 88%. The thickness of diffusion layer and effective segregation coefficient of Fe,Ni,Cu and Ti were calculated under different temperature gradient conditions. The results show that the diffusion layer thickness and the effective segregation coefficient of metal impurities decreased with the increase of temperature gradient,which greatly improves the removal of impurity segregation,and improves the yield.
引文
[1]Istratov A A,Hieslmair H,Weber E R.Iron and its complexes in silicon[J].Applied Physics A,1999,69(1):13-44.
[2]杨德仁.太阳电池材料[M].北京:化学工业出版社,2009.145-146.
[3]Yu Wenzhou,Ma Wenhui,Lyu Guoqiang,et al.Lowcost process for silicon purification with bubble adsorption in Al-Si melt[J].Metallurgical and Materials Transactions B-Process Metallurgy and Materials Processing Science,2014,45(4):1573-1578.
[4]Zhang Jianmin,Lu Yiping,Ma X D,et al.Purifying multicrystalline silicon by directional solidification method with induced electromagnetic field[J].Materials Science&Technology,2011,27(1):440-445.
[5]Ren Shiqiang,Li Pengting,Jiang Dachuan,et al.Removal of Cu,Mn and Na in multicrystalline silicon by directional solidification under low vacuum condition[J].Vacuum,2015,115:108-112.
[6]邢其智.中频感应熔炼条件下多晶硅定向凝固铸锭研究[D].大连:大连理工大学,2011.[6]Xing Qizhi.Multi-crystalline silicon ingot casting by directional solidification using medium-frequency induction melting[D].Dalian:Dalian University of Technology,2011.
[7]Li Pengting,Ren Shiqiang,Jiang Dachuan,et al.Effect of alternating magnetic field on the removal of metal impurities in silicon ingot by directional solidification[J].Journal of Crystal Growth,2016,437:14-19.
[8]Cablea M,Zaidat K,Gagnoud A,et al.Directional solidification of silicon under the influence of travelling magnetic field[J].Journal of Crystal Growth,2014,401:883-887.
[9]李天佑,杜海文,费宏明,等.隔热笼提升速度对高效多晶硅定向凝固的影响[J].铸造技术,2017,(10):2339-2343.[9]Li Tianyou,Du Haiwen,Fei Hongming,et al.Effects of rising speed of heat insulation on high-efficiency multicrystalline silicon ingot directional solidification[J].Foundry Technology,2017,(10):2339-2343.
[10]刘志辉,罗玉峰,龚洪勇,等.降温速率对升级冶金硅定向凝固生长多晶硅少子寿命的影响[J].人工晶体学报,2017,46(1):13-17.[10]Liu Zhihui,Luo Yufeng,Gong Hongyong,et al.Influence of cooling rate on the minority carrier lifetime of multicrystalline silicon grown with metallurgical grade silicon feedback by directional solidification[J].Journal of Synthetic Crystals,2017,46(1):13-17.
[11]蔡莉莉,冯翠菊,王会彬.多晶硅锭定向凝固过程的温度场模拟[J].材料科学与工程学报,2015,33(1):117-121.[11]Cai Lili,Feng Cuiju,Wang Huibin.Numerical simulation of temperature field in directional solidification process of polysilicon Ingot[J].Journal of Material Science&Engineering,2015,3(1):117-121.
[12]Zhao Baitong,Gao Wenxiu,Jia Chengchang.Research on ingot casting process and properties of poly-silicon[J].Advanced Materials Research,2013,772:739-743.
[13]傅恒志.先进材料定向凝固[M].北京:科学出版社,2008.[13]Fu Hengzhi.Directional solidification and processing of advanced materials[M].Beijing:Beijing Science Press,2008.
[14]李鹏廷,王凯,姜大川,等.冶金法制备太阳能级多晶硅的耦合除杂研究[J].无机材料学报,2017,32(3):281-286.[14]Li Pengting,Wang Kai,Jiang Dachuan,et al.Coupling of metallurgical method to remove impurities in solar grade polycrystalline silicon[J].Journal of Inorganic Materials,2017,32(3):281-286.
[15]Li Pengting,Ren Shiqiang,Jiang Dachuan,et al.Distributions of substitutional and interstitial impurities in silicon ingot with different grain morphologies[J].Materials Science in Semiconductor Processing,2017,67:1-7.
[16]吕东,马文会,伍继君,等.冶金法制备太阳能级多晶硅新工艺原理及研究进展[J].材料导报,2009,23(05):30-33.[16]Lyu Dong,Ma Wenhui,Wu Jijun,et al.New process principle and research advances of production of solar grade poly silicon by metallurgical method[J].Materials Review,2009,23(5):30-33.
[2]杨德仁.太阳电池材料[M].北京:化学工业出版社,2009.145-146.
[3]Yu Wenzhou,Ma Wenhui,Lyu Guoqiang,et al.Lowcost process for silicon purification with bubble adsorption in Al-Si melt[J].Metallurgical and Materials Transactions B-Process Metallurgy and Materials Processing Science,2014,45(4):1573-1578.
[4]Zhang Jianmin,Lu Yiping,Ma X D,et al.Purifying multicrystalline silicon by directional solidification method with induced electromagnetic field[J].Materials Science&Technology,2011,27(1):440-445.
[5]Ren Shiqiang,Li Pengting,Jiang Dachuan,et al.Removal of Cu,Mn and Na in multicrystalline silicon by directional solidification under low vacuum condition[J].Vacuum,2015,115:108-112.
[6]邢其智.中频感应熔炼条件下多晶硅定向凝固铸锭研究[D].大连:大连理工大学,2011.[6]Xing Qizhi.Multi-crystalline silicon ingot casting by directional solidification using medium-frequency induction melting[D].Dalian:Dalian University of Technology,2011.
[7]Li Pengting,Ren Shiqiang,Jiang Dachuan,et al.Effect of alternating magnetic field on the removal of metal impurities in silicon ingot by directional solidification[J].Journal of Crystal Growth,2016,437:14-19.
[8]Cablea M,Zaidat K,Gagnoud A,et al.Directional solidification of silicon under the influence of travelling magnetic field[J].Journal of Crystal Growth,2014,401:883-887.
[9]李天佑,杜海文,费宏明,等.隔热笼提升速度对高效多晶硅定向凝固的影响[J].铸造技术,2017,(10):2339-2343.[9]Li Tianyou,Du Haiwen,Fei Hongming,et al.Effects of rising speed of heat insulation on high-efficiency multicrystalline silicon ingot directional solidification[J].Foundry Technology,2017,(10):2339-2343.
[10]刘志辉,罗玉峰,龚洪勇,等.降温速率对升级冶金硅定向凝固生长多晶硅少子寿命的影响[J].人工晶体学报,2017,46(1):13-17.[10]Liu Zhihui,Luo Yufeng,Gong Hongyong,et al.Influence of cooling rate on the minority carrier lifetime of multicrystalline silicon grown with metallurgical grade silicon feedback by directional solidification[J].Journal of Synthetic Crystals,2017,46(1):13-17.
[11]蔡莉莉,冯翠菊,王会彬.多晶硅锭定向凝固过程的温度场模拟[J].材料科学与工程学报,2015,33(1):117-121.[11]Cai Lili,Feng Cuiju,Wang Huibin.Numerical simulation of temperature field in directional solidification process of polysilicon Ingot[J].Journal of Material Science&Engineering,2015,3(1):117-121.
[12]Zhao Baitong,Gao Wenxiu,Jia Chengchang.Research on ingot casting process and properties of poly-silicon[J].Advanced Materials Research,2013,772:739-743.
[13]傅恒志.先进材料定向凝固[M].北京:科学出版社,2008.[13]Fu Hengzhi.Directional solidification and processing of advanced materials[M].Beijing:Beijing Science Press,2008.
[14]李鹏廷,王凯,姜大川,等.冶金法制备太阳能级多晶硅的耦合除杂研究[J].无机材料学报,2017,32(3):281-286.[14]Li Pengting,Wang Kai,Jiang Dachuan,et al.Coupling of metallurgical method to remove impurities in solar grade polycrystalline silicon[J].Journal of Inorganic Materials,2017,32(3):281-286.
[15]Li Pengting,Ren Shiqiang,Jiang Dachuan,et al.Distributions of substitutional and interstitial impurities in silicon ingot with different grain morphologies[J].Materials Science in Semiconductor Processing,2017,67:1-7.
[16]吕东,马文会,伍继君,等.冶金法制备太阳能级多晶硅新工艺原理及研究进展[J].材料导报,2009,23(05):30-33.[16]Lyu Dong,Ma Wenhui,Wu Jijun,et al.New process principle and research advances of production of solar grade poly silicon by metallurgical method[J].Materials Review,2009,23(5):30-33.