Method for crucible-free zone melting using a displaced heater
Abstract
Abstract IN A METHOD OF ZONE MELTING A SEMICONDUCTOR ROD, THE ROD IS SUBSTANTIALLY VERTICALLY SUPPORTED AT ONE END BY A FIRST END HOLDER LOCATED IN THE SUBSTANTIALLY VERTICAL AXIS OF THE ROD, A SEED CRYSTAL BEING ATTACHED TO THE OTHER END OF THE ROD AND HAVING A FREE END SUPPORTED BY A SECOND END HOLDER, AND A MOLTEN ZONE IS FORMED IN THE ROD BY AN ANNULAR HEATING DEVICE SURROUNDING THE ROD AND DIVIDING IT INTO TWO ROD PORTIONS, THE ANNULAR HEATING DEVICE AND THE ROD BEING MOVED RELATIVE TO ONT ANOTHER IN THE AXIAL DIRECTION OF THE ROD FROM THE SEED CRYSTAL TO THE FIRST END HOLDER SO THAT ONE OF THE PORTIONS OF THE ROD IS SUPPLIED TO THE MELT AND THE OTHER PORTION THEREOF CRYSTALLIZES OUT OF THE MELT. THE IMPROVEMENT IN THE METHOD INCLUDES LATERALLY DISPLACING THE ANNULAR HEATING DEVICE TO A POSITION ECCENTRIC TO THE AXIS OF THE ROD BUT NEVERTHELESS STILL SURROUNDING THE ROD, AND MAINTAINING THE ECCENTRIC RELATIONSHIP OF THE ANNULAR HEATING DEVICE TO THE ROD FOR AT LEAST PART OF THE MOLTEN ZONE PASS ALONG THE ROD.
Inventors
- 👤 Wolfgang Keller
- 👤 Konrad Reuschel
Bibliographic Details
Claims Analysis
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