Patent ID: 7282094
Filing Date: 2007-10-16
Classification: C30B,Y10T

Abstract:
1. A computer-based simulation method for predicting the distribution of densities and sizes of void defects in a single crystal, the method comprising: a first step of applying a mesh onto each member in a hot zone of a pulling-up machine ( a second step of classifying mesh points according to individual members of the hot zone, assigning to mesh points classified to a given member a property value peculiar to the member, determining the pulled-up length of the single crystal ( a third step of determining the distribution of temperatures over the surface of the members of hot zone based on the heat amount generated by a heater and the radiation rate of the members; a fourth step of determining the distribution of internal temperatures of the members of hot zone by solving a heat conduction equation based on the distribution of temperatures over the surface of the members and their heat conductivities, and then solving an eddy current model equation in conjunction with a Navier-Stokes equation assuming that the melt ( a fifth step of determining the shape of the solid-liquid interface between the single crystal ( a sixth step of repeating steps a seventh step of altering stepwise the pulled-up length and height of single crystal ( an eighth step of dividing, at specified intervals, the period from a time when the single crystal ( a ninth step of determining the distribution of densities of air holes and inter-lattice atoms within single crystal ( a tenth step of determining the temperature at which voids ( an eleventh step of determining the density of voids ( a twelfth step of determining the radius of voids ( a thirteenth step of determining the temperature at which inner wall oxide membrane ( a fourteenth step of determining the radius of voids ( a fifteenth step of repeating steps