Removal of phosphorus by the solidification refining with Si—Al melts

Abstract

To discuss the possibility of phosphorus removal from silicon by the solidification refining with Si -Al melts, the distribution of phosphorus between solid silicon and the liquid Si-Al alloy at 1173-1373 K was investigated. In the present study, the distribution of phosphorus was examined by the temperature gradient zone melting method, where a phosphorus containing molten Si -Al zone was passed through a single crystalline silicon phase. The segregation ratio of phosphorus at its infinite dilution was obtained as 0.12 (1373 K), 0.085 (1273 K) and 0.061 (1173 K), respectively, and the solidification refining with the Si -Al melts was found to be effective for the removal of phosphorus at lower temperature. q

Numerical study of the crystallization of pure material from solution with impurity

“…В работах [4][5][6] показано, что зависимость коэффициентов сегрега-ции k(T ) компонентов B, P от температуры в системе Si-Al с высокой точностью можно считать линейной:…”

A Thermochemical Database for the Solar Cell Silicon Materials

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Effects of Applied Power on Temperature of Electromagnetic Levitation of Silicon and Silicon-Iron Droplets

“…At present, an expensive grade of silicon for semiconductor is used for solar cell to convert solar energy into electricity. The use of expensive raw material for photovoltaic industry results in a high cost of photovoltaic electricity, the cost of which is five-time higher than that of the electricity from conventional electricity generation [2][3][4].To upgrade metallurgical silicon to solar grade silicon, a great number of research works have been carried out in this field of using relative inexpensive raw material, metallurgical grade silicon, as a starting materials for the production of solar grade silicon is one of the most economical way to make solar cells [1][2][3][4][5][6]. Solidification refining is an effective way to remove most impurities in molten silicon, which doesn't need any chemical reaction, with the exception of phosphorus and boron [7][8][9][10][11].…”