Patent ID: 6210477
Filing Date: 2001-04-03
Classification: C30B,Y10S,Y10T

Abstract:
A method for pulling a single crystal from a melt, using an apparatus for pulling a single crystal comprising a crucible charged with a melt, a heater located around the crucible, and a straightening vane having a body surrounding a pulled single crystal, said straightening vane has the shape of an inverted truncated cone or a cylinder in which the upper and lower planes are removed, said straightening vane is located above the crucible and has a lower end portion, wherein the distance between the lower end portion of the straightening vane body and the surface of the melt charged in the crucible, said distance is called the gap, is variable, said method comprising:raising the temperature of the front portion of a seed crystal into the range of 1380-1480.degree. C., via heat from the heater surrounding the crucible, wherein the gap is set in the range of 30-200 mm and the seed crystal has a diameter of 5-15 mm and is a pillar;bringing the seed crystal into contact with the melt without further lowering the seed crystal after contact with the melt; andpulling a single crystal without forming a neck.