| 摘要 |
PROBLEM TO BE SOLVED: To provide a production method of a silicon single crystal ingot in which changes in crystal qualities are suppressed in a crystal axis direction. SOLUTION: In the production of a silicon single crystal ingot 25 by pulling from a silicon melt 12 doped with nitrogen, a pull-up speed of pulling the ingot in a bottom side is increased than a pull-up speed of pulling the ingot in a top side so as to control a V/G ratio (a ratio of the pull-up speed to the temperature gradient) of pulling the bottom side ingot to be larger than a V/G ratio of pulling the top side ingot so as to produce a silicon single crystal ingot having a region where a vacancy-type point defect is induced in at least the center of a cross-sectional plane and having the outer diameter of the bottom side ingot larger than the outer diameter of the top side ingot. Since the outer diameter of the bottom side ingot is made larger than the outer diameter of the top side ingot, OSF (oxidation-induced stacking faults) generating in an outer peripheral part of the ingot can be enclosed in a region outside the outer diameter of the bottom ingot after cutting the ingot. COPYRIGHT: (C)2010,JPO&INPIT
|
