[14a-F201-1~11] 15.7 Crystal evaluation, impurities and crystal defects

▲ [14a-F201-6] Numerical analysis on the free surface of floating zone (FZ) for silicon crystal growth by Volume of Fluid (VOF) model

〇(P)Xuefeng Han¹, Satoshi Nakano¹, Xin Liu¹, Koichi Kakimoto¹ (1.RIAM, Kyushu Univ.)

Keywords:floating zone, silicon, crystal growth

In the floating zone process, a good controllability of the molten silicon shape is important for successful crystal growth. Therefore, previous studies have investigated the shape of free surface by solving Young-Laplace equation in 2D axisymmetric model. With the development of floating zone technique and requirement of dopant control, the crystal below the molten silicon is not coaxial with feed. Hence the previous studies focusing on 2D axisymmetric calculation of the shape of free surface could not accurately predict the shape of free surface. By employing volume of fluid (VOF) model, 3D calculation results of free surface can be obtained. It is observed that asymmetric shape of free surface is formed if the feed rod and crystal are not coaxial.