Patent ID: 7323053

Claim:
A pulling-down apparatus including a melting pot having a narrow hole at the bottom side thereof, an induction heating device, arranged around the melting pot, for heating the melting pot, and a seed-holding device, extending vertically, for holding at the top end thereof a seed that contacts a melt material that flows out through the narrow hole and determines a crystal orientation for the melt material, the pulling-down apparatus comprising: a vacuum container, having a plurality of observation windows through which a solid-liquid interface where the melt material is crystallized can be observed from different directions, for containing the melting pot, the induction heating device, and the seed-holding device and enabling air therein to be discharged; a driving mechanism for supporting the seed-holding device at the bottom end of the seed-holding device, configuring part of the inner wall of the vacuum container, and enabling the bottom end of the seed-holding device to be driven in different directions on an approximately horizontal plane; a pulling-down mechanism for supporting the driving mechanism and approximately vertically moving the seed-holding device, by way of the driving mechanism; and a plurality of imaging devices that are arranged outside the respective plurality of observation windows and whose image-pickup light axes correspond with the respective different directions, wherein the respective image-pickup light axes of the imaging devices are perpendicular on an approximately horizontal plane to the driving directions in which the bottom end of the seed-holding device is driven on the approximately horizontal plane, and the solid-liquid interface is observed from the different directions by the plurality of imaging devices to obtain an angle between the horizontal plane and the solid-liquid interface, and the seed-holding device is shifted in parallel with a direction perpendicular to each image-pickup light axis on the basis of the angle without pivoting the seed-holding device so as to keen the solid-liquid interface horizontal.