Purifying method for recycled P/N mixed type silicon material having unknown resistance

• Main Authors: CAI, JIN-FENG, CHEN, RONG-QUAN, HUANG, ZHEN-NAN
• Format: Patent
• Language: Chinese; English
• Published: 01.10.2010
• Subjects: CHEMISTRY; COMPOUNDS THEREOF; INORGANIC CHEMISTRY; METALLURGY; NON-METALLIC ELEMENTS

The invention relates to a purifying method for recycled P/N mixed type silicon material having unknown resistance. The method includes the following steps: a first step of categorizing the silicon material to a normal type silicon material or an abnormal type silicon material; a second step of filling material; a third step of implementing the crucible; a fourth step of vacuuming a crystal growth furnace; a fifth step of heating the crystal growth furnace; a sixth step of back-filling pressure: back-filling vacuum pressure to the heated crystal growth furnace in the fifth step with inert gas and raising the temperature within the crystal growth furnace; a seventh step of temperature lowering: lowering the temperature of the crystal growth furnace in the sixth step and performing directional solidification so that the solidified silicon material includes a recycling part and a disposal part; the eighth step of annealing the crystal growth furnace; the ninth step of cooling the annealed silicon material in the