Method and apparatus for forming ingots of a semiconductor alloy

• Main Author: LANCASTER, ROBERT A
• Format: Patent
• Language: English; French; German
• Published: 30.12.1981
• Subjects: AFTER-TREATMENT OF SINGLE CRYSTALS OR A HOMOGENEOUSPOLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; APPARATUS THEREFOR; CASTING; CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES; CHEMISTRY; CRYSTAL GROWTH; METALLURGY; PERFORMING OPERATIONS; POWDER METALLURGY; PRODUCTION OF A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITHDEFINED STRUCTURE; REFINING BY ZONE-MELTING OF MATERIAL; SINGLE CRYSTALS OR HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITHDEFINED STRUCTURE; SINGLE-CRYSTAL-GROWTH; TRANSPORTING; UNIDIRECTIONAL SOLIDIFICATION OF EUTECTIC MATERIAL ORUNIDIRECTIONAL DEMIXING OF EUTECTOID MATERIAL

In connection with a method and an apparatus for controlled directional solidification of semiconductor alloys of at least two constituents the method comprises heating at least two different constituents so that they are combined in a liquid phase molten material of uniform composition with at least a portion of the molten material lying in a plane, and rapidly cooling at least a portion of the molten material so that a planar solidification front passes rapidly through at least a portion of the molten material in a direction perpendicular to the plane until at least a portion of the molten material is rapidly solidified. The apparatus comprises a vessel (13) for containing the constituents (22) of the alloy, the vessel having an interior planar surface (20). Also included is heating apparatus (35,40) for heating the constituents in the vessel so that a liquid phase molten material of uniform composition is formed. The apparatus further comprises cooling apparatus (71-73) for rapidly supplying uniform cooling to the interior planar surface in order to cause rapid solidification in at least a portion of the molten material, whereby a planar solidification front passes rapidly through at least a portion of the molten material in a direction perpendicular to the interior planar surface of the vessel.