热屏位置对熔体流场及氧迁移路径的影响OA

Monocrystalline silicon components serve as core parts of semiconductor equipment and are widely used in various high-temperature manufacturing processes of integrated circuits.Oxygen content dominates their performance and service life.With distinct control standards for different application scenarios,precise oxygen control is critical to industrial development.This paper investigates the influence of thermal shield position on the argon flow field,melt flow field and temperature field,and further reveals the internal mechanism of the synergistic effect between the melt flow field and temperature field on the dissolution capacity,migration flux and migration path of oxygen impurities.The results show that reducing the spacing between the thermal shield and the crystal can increase the argon flow velocity near the triple-phase point,enhance crystal heat dissipation,stabilize the growth interface and improve the removal efficiency of oxygen impurities.Meanwhile,it homogenizes the melt temperature field,inhibits quartz crucible dissolution,optimizes melt turbulent viscosity,and weakens the transport and migration of oxygen impurities in the melt.In addition,compact small eddies form on the melt surface,altering the migration path of oxygen impurities.Under the combined effect of melt flow field and temperature field,the maximum radial oxygen content of the crystal decreases by 0.275×1017 atoms/cm3,and the average value decreases by 0.206×1017 atoms/cm3.