METHOD FOR PRODUCING GaAs SINGLE CRYSTAL

• Main Authors: TAIHO KOJI, OWADA MASASHI, SUZUKI TAKASHI
• Format: Patent
• Language: English
• Published: 07.09.2006
• Subjects: AFTER-TREATMENT OF SINGLE CRYSTALS OR A HOMOGENEOUSPOLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; APPARATUS THEREFOR; CHEMISTRY; CRYSTAL GROWTH; 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; UNIDIRECTIONAL SOLIDIFICATION OF EUTECTIC MATERIAL ORUNIDIRECTIONAL DEMIXING OF EUTECTOID MATERIAL

PROBLEM TO BE SOLVED: To prevent the assembly of dislocations causing crystal defects and the polycrystallization by making the shape of the solid-liquid interface stable and flat without lowering the crystal growth speed when the shoulder part of a crystal being pulled is formed. SOLUTION: The periphery of a seed crystal in a crucible is covered with an umbrella-like heat insulation cover having a flat top part. Thereby, the temperature change in the vicinity of the shoulder part in the pulling direction of the crystal can be suppressed small when the shoulder part is formed, and the temperature change in the vicinity of the shoulder part in the direction perpendicular to the pulling direction of the crystal can be also suppressed small. COPYRIGHT: (C)2006,JPO&NCIPI