| 摘要 |
PROBLEM TO BE SOLVED: To provide polycrystalline silicon which is less expensive to produce than compact silicon rod but nevertheless exhibits good performance in a CZ crystal pulling method.SOLUTION: A polycrystalline silicon rod has a total diameter of at least 150 mm, and includes a core (A) having porosity of 0 to less than 0.01 around a thin rod, and at least two subsequent regions B and C which differ in porosity by a factor of 1.7 to 23, the outer region C being less porous than the region B. |
