MANUFACTURE OF EPITAXIAL SILICON WAFER

• Main Author: NINOMIYA MASAHARU
• Format: Patent
• Language: English
• Published: 23.03.2001
• Edition: 7
• Subjects: AFTER-TREATMENT OF SINGLE CRYSTALS OR A HOMOGENEOUSPOLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; APPARATUS THEREFOR; BASIC ELECTRIC ELEMENTS; CHEMISTRY; CRYSTAL GROWTH; ELECTRIC SOLID STATE DEVICES NOT OTHERWISE PROVIDED FOR; ELECTRICITY; METALLURGY; PRODUCTION OF A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITHDEFINED STRUCTURE; REFINING BY ZONE-MELTING OF MATERIAL; SEMICONDUCTOR DEVICES; 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 provide a manufacturing method superior in IG(intrinsic gettering) capability, where no BMD(bulk micro defect) if formed near the surface of silicon wafer for relatively a short processing time, by suppressing uneven formation of the oxygen deposition nucleus of a epitaxial silicon wafer provided with IG capability. SOLUTION: A latent nucleus is allowed to be produced and brown over the entire crystal in a low-temperature process, then the latent nucleus on a substrate surface is allowed to contract and dissolve in a thermal process at a medium temperature, while BMD is allowed to grow and form inside the substrate. Thus the BMD appears inside a wafer instead of at the surface layer part of it, for less variations in BMD density in a crystal growth method. When an epitaxial film is formed at the substrate, the BMD is formed only inside the substrate without surface defects.