Movable partition designed for the seed-assisted silicon ingot casting in directional solidification process

摘要

For the seed-assisted casting process for silicon ingots, different partition blocks were designed in the directional solidification (DS) furnaces to preserve the seed crystals and optimize the thermal field in the hot-zone. A transient global model was established to investigate the effects of different partition blocks during the solidification process. The simulation results showed that the partition blocks can significantly influence the temperature distributions and the melt flow fields. From the designed partition blocks, the movable partition block was more favorable for the seedassisted DS process. A suitable temperature gradient and a flat seed-melt (s-m) interface were obtained, which facilitated the preservation of seed crystals effectively, and an optimized crystal-melt (c-m) interface was achieved as well. One of the designs of the movable partition blocks was implemented in quasi-mono crystalline silicon casting experiments and it has been confirmed that the designed movable partition block was helpful for the improvement of the single crystal area.