| 摘要 |
PROBLEM TO BE SOLVED: To provide a silicon single crystal not bursting during growing and having no growing faults. SOLUTION: The temperature gradients along the axial direction at the center and the outer periphery of a silicon single crystal 11 in the temperature range of 1,370-1,310°C are taken as Gc<SB>1</SB>and Ge, and the outer periphery of the growing single crystal is cooled to make the ratio Gc<SB>1</SB>/Ge become 1.2-1.3. No COP nor dislocation clusters are generated by controlling the ratio v/Gc<SB>2</SB>constant so that the crystal comprises a perfect region without the aggregates of interstitial silicon type point defects and of hole type point defects, wherein the gap between the bottom end of a heat shield surrounding the peripheral surface of the single crystal and the surface of a silicon melt liquid 15 is set at 40-100 mm, and the pulling speed of the single crystal is represented by v and the temperature gradient along the axial direction at the center of the single crystal from its melting temperature to 1,350°C is represented by Gc<SB>2</SB>. Controlling the pulling speed of the single crystal makes the heat stress at the center of the single crystal above the solid-liquid interface 33 set at not higher than 50 MPa. COPYRIGHT: (C)2010,JPO&INPIT
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