Growth of Czochralski silicon under magnetic field  

作　　者：XU Yuesheng LIU Caichi WANG Haiyun ZHANG Weilian YANG Qingxin LI Yangxian REN Binyan LIU Fugui 

机构地区：[1]Institute of Information Function Materials, Hebei University of Technology, Tianjin 300130, China

出　　处：《Science China(Technological Sciences)》2004年第3期281-292,共12页中国科学(技术科学英文版)

基　　金：the National Natural Science Foundation of China (Grant No. 59972007); the Ministry of National Science and Technology and the Natural Science Foundation of Hebei Province (No.599033).

摘　　要：Growth of Czochralski (CZ) silicon crystals under the magnetic field induced by a cusp-shaped permanent magnet of NdFeB has been investigated. It is found that the mass transport in silicon melt was controlled by its diffusion while the magnetic intensity at the edge of a crucible was over 0.15 T. In comparison with the growth of conventional CZ silicon without magnetic field, the resistivity homogeneity of the CZ silicon under the magnetic field was improved. Furthermore, the Marangoni convection which has a significant influence on the control of oxygen concentration was observed on the surface of silicon melt. It is suggested that the crystal growth mechanism in magnetic field was similar to that in micro-gravity if a critical value was reached, named the growth of equivalent micro-gravity. The relationship of the equivalent micro-gravity and the magnetic intensity was derived as g=(v0/veff)g0. Finally, the orders of the equivalent micro-gravity corresponding to two crucibles with characteristic sizes were calculated.Growth of Czochralski (CZ) silicon crystals under the magnetic field induced by a cusp-shaped permanent magnet of NdFeB has been investigated. It is found that the mass transport in silicon melt was controlled by its diffusion while the magnetic intensity at the edge of a crucible was over 0.15 T. In comparison with the growth of conventional CZ silicon without magnetic field, the resistivity homogeneity of the CZ silicon under the magnetic field was improved. Furthermore, the Marangoni convection which has a significant influence on the control of oxygen concentration was observed on the surface of silicon melt. It is suggested that the crystal growth mechanism in magnetic field was similar to that in micro-gravity if a critical value was reached, named the growth of equivalent micro-gravity. The relationship of the equivalent micro-gravity and the magnetic intensity was derived as g=(v0/veff)g0. Finally, the orders of the equivalent micro-gravity corresponding to two crucibles with characteristic sizes were calculated.

关 键 词：Magnetic field equivalent micro-gravity diffusion-controlled mechanism Marangoni convection. 

分 类 号：TH[机械工程]