四极磁场下大尺寸直拉硅单晶生长三维数值模拟  

Three-dimensional numerical simulation of large diameter Czochralski silicon growth in a quad-pole magnetic field

作　　者：张晶[1] 刘丁[1] 赵跃[1] 惠一龙 姜雷[1] 

机构地区：[1]西安理工大学国家联合晶体生长设备及系统集成工程研究中心,陕西西安710048

出　　处：《材料热处理学报》2015年第9期238-243,共6页Transactions of Materials and Heat Treatment

基　　金：国家重点基础研究发展计划(2014CB360508);博士点基金优先发展领域(20136118130001)

摘　　要：在大尺寸直拉硅单晶生长过程中,针对水平磁场单方向磁力线分布引起的熔体温度分布非轴对称特征,提出了一种双磁力线结构的磁场——四极磁场。为准确描述非轴对称磁场作用下晶体生长过程,采用三维数值模拟方法,建立了四极磁场下二维/三维混合热场模型的边界条件,并将三维数值模拟结果与水平磁场作以对比。结果表明,四极磁场降低了熔体内部温度的非轴对称性;增加磁感应强度有利于增加熔体自由表面附近温度分布的均匀性,但对固液界面形状调节作用不明显;强磁场环境下,提高晶体旋转速度有利于改变固液界面凹凸程度,改善固液界面形态的非轴对称性。In large diameter Czochralski silicon crystal growth process, for the non axial symmetric features in melt temperature caused by the unidirectional magnetic flux distribution, a magnetic field with dual flux line structure is proposed the quad-pole magnetic field. A three dimensional numerical simulation method is used to describe the growth process of the crystal growth process under the non axial symmetric magnetic field. The boundary conditions of 2D/3D hybrid hot zone model with quad-pole magnetic field are established and the 3D numerical results are compared with the bi-pole horizontal magnetic field hot zone. The results shows that in quad-pole magnetic fieht, the non-axial symmetry of the internal temperature of the melt is reduced; Increasing the magnetic flux density helps to improve the temperature distribution uniformity near the free surface of the melt, but improvements on the shape of solid-liquid interface is not obvious ; Under strong magnetic flux density, a higher crystal rotation rate will helps improve the deflection of the solid-liquid interface, and improve the non-axial symmetry of the solid-liquid interface shape.

关 键 词：直拉硅单晶 非轴对称性 四极磁场 数值模拟 

分 类 号：TG139.8[一般工业技术—材料科学与工程]