论文部分内容阅读
研究了磁场直拉硅单晶生长.采用钕铁硼(NdFeB)永磁磁体,向硅熔体所在空间引入Cusp磁场.当坩埚边缘磁感应强度达到0.15T时,熔硅中杂质输运受扩散控制.熔硅自由表面观察到明显的Marangoni对流;硅单晶纵向、径向电阻率均匀性得到改善;控制Marangoni对流,可灵活控制硅单晶中的氧浓度.把磁场拉晶同硅单晶的等效微重力生长联系起来,推导出了引入磁感应强度和对应等效微重力等级的关系式g=v0/veff·g0,并针对坩埚的两种特征尺寸,进行了直拉硅单晶等效微重力等级的计算.
The magnetic field of Czochralski silicon growth was studied. The NdFeB permanent magnet was used to introduce Cusp magnetic field into the space where the silicon melt was located. When the magnetic induction of the edge of the crucible reached 0.15T, the impurity transport in the silicon melt was controlled by diffusion The apparent Marangoni convection is observed on the free surface of the molten silicon, the longitudinal and radial resistivity uniformity of the silicon single crystal is improved, and the Marangoni convection can be controlled flexibly to control the oxygen concentration in the silicon single crystal. Equivalent microgravity growth, the relationship g = v0 / veff · g0 was deduced to introduce the magnetic flux density and corresponding equivalent microgravity grading. According to the two feature sizes of the crucible, the Czochralski silicon single crystal equivalent Microgravity level calculation.