| 摘要 |
PURPOSE:To purify a primary crystal silicon crystallized from a hypereutectic aluminum-silicon alloy melt to a high purity at a temperature within the range of g 1000 deg.C and < the melting point of the silicon without using a melt such as a slag and passing through a separating step. CONSTITUTION:This method for purifying silicon is to pulverize a primary crystal silicon having <=10000wt.ppm aluminum content and <=10wt.ppm iron content, regulate the particle diameter to 1-1000mum, wash the resultant particles with an inorganic acid, subsequently heat-treat the washed particles in an atmospheric gas at >=1000 deg.C and < the melting point of the silicon under <=1X10<-2>atm partial pressure of oxygen, then melt the silicon and carry out the orienting solidification. |
