Impurity segregation in directional solidified multi-crystalline silicon

Effect of accelerated crucible rotation on the segregation of impurities in vertical Bridgman growth of multi-crystalline silicon

“…The concepts of the numerical model, operating system and physical material properties are the same as in our previous study and described in detail in [18]. The effect of ACRT on the impurity segregation has been limited to two impurities, carbon and oxygen.…”

“…Primarily, warmer fluid is ascending near the crucible wall and cooler fluid descending at the center line forming the upper vortex. Secondarily, a curved solid/liquid interface with a concave shape occurs and the buoyancy due to the radial temperature gradient drives a flow parallel to the interface towards the center of the melt [18]. The spin-up of an isothermal fluid in a crucible basically causes a vortex in clockwise direction, while the spin-down causes a vortex in counterclockwise direction if the crucible is accelerated from rest or decelerated from a constant rotation rate [2,19].…”

Optimization of silicon crystallization in a Bridgman growth furnace by numerical modeling

“…Although these aspects require 3D models of the crystallization process, current models are often limited to 2D simulation (assuming axisymmetric conditions or planar configurations) or quasi-stationary models [1][2][3][4][5][6][7][8][9][10][11][12].…”

Effects of argon flow on melt convection and interface shape in a directional solidification process for an industrial-size solar silicon ingot

“…The argon flow and silicon melt strongly interact with each other through the melt-gas (m-g) interface [2]. They both influence the global heat transfer, the melt-crystal (m-c) interface shape and the impurity transport pathway through the DS process [3][4][5]. As the parameters of argon flow, such as the flow rate and the furnace pressure, are easily adjusted in the DS process, its effect on the silicon melt convection is adjustable.…”