US 12,435,443 B2
Method and apparatus for manufacturing defect-free monocrystalline silicon crystal
Keiichi Takanashi, Saga (JP); and Ippei Shimozaki, Imari (JP)
Assigned to SUMCO Corporation, Tokyo (JP)
Filed by SUMCO Corporation, Tokyo (JP)
Filed on Mar. 6, 2023, as Appl. No. 18/117,981.
Application 18/117,981 is a continuation of application No. 17/037,060, filed on Sep. 29, 2020, granted, now 11,618,971.
Prior Publication US 2023/0228000 A1, Jul. 20, 2023
Int. Cl. C30B 15/20 (2006.01); C30B 15/10 (2006.01); C30B 35/00 (2006.01)
CPC C30B 35/002 (2013.01) [C30B 15/10 (2013.01); C30B 15/20 (2013.01)] 13 Claims
OG exemplary drawing
 
1. A method of growing a silicon crystal, comprising:
preparing a silicon melt in a crucible, wherein a gap exists between a surface of the silicon melt and a heat shield above the surface of the silicon melt;
rotationally pulling the silicon crystal from the silicon melt at a pull speed, the silicon crystal having a diameter;
accessing a margin profile, the margin profile including Pv-Pi margin data corresponding to each of various lengths of the silicon crystal; and
determining adjustments to the gap using the Pv-Pi margin data in response to changes in the pull speed of the silicon crystal from the silicon melt, wherein each of the Pv-Pi margin data includes ranges of the gap versus the pull speed which define a defect-free region on the silicon crystal at a given crystal length.