Design of a high temperature superconducting magnet for a single silicon crystal growth system

This paper presents a study on the design of a high-temperature superconducting (HTS) magnet for a Czochralski single silicon-crystal growth system by evaluating the temperature and flow distributions of silicon melt at the cusp magnetic field. A two-dimensional finite element method (FEM) simulation model was built to determine the effects of the magnetic field on the temperature and flow distributions in the silicon melt. The characteristics of the HTS magnet were analyzed using a three-dimensional FEM model. The HTS magnet was designed using 2G HTS wire and the magnet was validated through FEM simulation. The simulation results showed that the melt convection was significantly suppressed by the Lorentz force, and that the temperature distribution was uniform in the silicon melt under the cusp magnetic field. The shape of the HTS magnet was determined as a magnet ring with a magnetic flux density of 0.35 T at the center of the crucible bottom. The fundamental design specifications and the data obtained from this study can be applied to the development of a real silicon-crystal growth system. (paper)