METHOD OF CONTINUOUSLY PULLING UP SILICON SINGLE CRYSTAL FREE FROM AGGLOMERATES OF POINT DEFECTS

摘要

PROBLEM TO BE SOLVED: To stably make an ingot into perfect area [P] over whole length in a high yield and to make oxygen concentration and electrical resistance of the ingot uniform over the whole length. SOLUTION: When an area where the agglomerates of interstitial silicon-type point defects are present in an ingot is defined as [I], an area where the agglomerates of vacancy-type point defects are present is defined as [V] and a perfect area free from the agglomerates of interstitial silicon-type point defects and the agglomerates of vacancy-type point defects is defined as [P], a silicon single crystal ingot 25 composed of such perfect area [P] is pulled up by a CZ method while controlling V/G (V: pulling up velocity; G: temperature gradient in the vertical direction of the ingot) to be constant. The ingot is pulled up from the inside area of an internal crucible 12 b while making only the V constant and while rotating the external crucible and rotating the ingot around the direction of the pulling up axis and, further, while supplying a silicon raw material 21 between the external crucible 12a for storing a silicon molten liquid 18 and the internal crucible 12b according to the amount of grown ingot.