Thermodynamics of solid silicon equilibrated with Si–Al–Cu liquid alloys

Thermodynamic Property of B in Molten Si and Phase Relations in the Si–Al–B System

“…(9) is obtained from eq. (8), where the slope of the linear relationship gives the interaction parameter between B and N in molten Si, taking the right hand side as ordinate and the B content as abscissa.…”

“…On the other hand, the present authors are trying to develop the Si refining process with Si-Al melt at low temperature, [6][7][8][9] where behavior, namely the precipitated phase, of concentrated B in Si-Al melt should be known for considering the removal of that phase by acid leaching. For the SiAl-B system, however, the phase diagram has been investigated by calculation phase diagram 10) and not clarified sufficiently.…”

Removal of B from Si by solidification refining with Si-Al melts

“…Also, the Ca-added acid leaching treatment, which is useful for removal of metallic impurities, is found to not be effective for B removal. [3] On the other hand, the present authors are trying to develop a solidification refining process for Si with an Si-Al melt at low temperatures [4][5][6][7][8] from the retrograde solidus line of impurities in Si, [9] which indicates the thermodynamic instability of impurities at lower temperatures. However, B removal in this refining has not been clarified thermodynamically.…”

“…Hence, the temperature-gradient-zone melting (TGZM) method [12] was employed as in the previous studies. [4][5][6] The segregation ratio of B between solid Si and the Si-Al melt, as well as the thermodynamic property of B in solid Si, was determined by measuring the Al distribution of solidified Si from the Si-Al melt zone. Figure 1 shows an experimental apparatus.…”

Continuous Solidification of Si from Si-Al Melt under the Induction Heating

“…On the other hand, the present authors have been trying to develop the Si solidification refining process with Si-Al melt at low temperature [2][3][4][5][6][7][8][9] by utilizing the thermodynamic instability of impurity elements in solid Si at lower temperature, which is expected from the retrograde solidus of Si. 10) This process is supposed as follows; (1) alloying MGSi with Al to obtain the Si-Al solvent (2) solidification of Si from the solvent (3) collection of the solidified Si crystals by the acid leaching.…”