热屏结构对直径400 mm直拉单晶硅生长的影响OA

Monocrystalline silicon is one of the key materials for the preparation of semiconductors.Driven by the need to reduce costs,large diameter and fast crystal pulling technology is one of the development trends in the preparation of monocrystalline silicon by Czochralski method.In this paper,a double thermal shield structure was proposed,and the effects of the double thermal shield structure on the temperature and gas flow fields,the melt-crystal interface,the growth rate of monocrystalline silicon,thermal stresses,and point defects during the growth of monocrystalline silicon were analyzed.The results demonstrate that the double thermal shield structure can guide the flow of argon gas near the solid-liquid interface,suppress vortex formation on the outer side of the thermal shield,enhance heat dissipation from the crystal,and consequently increase its growth rate,with a maximum improvement of 19.2%.At the same time,the double thermal shield structure also improves the melt-crystal interface fluctuation,and the maximum thermal stress is reduced by 4.266 MPa compared with the single thermal shield structure.Therefore,the double thermal shield structure has a better application prospect.