PROCESS FOR PRODUCING SILICON SINGLE-CRYSTAL, ANNEALED WAFER AND PROCESS FOR PRODUCING ANNEALED WAFER

• Main Authors: NAKAMURA, KOZO, NONAKA, SYUNJI, SHIRAISHI, YUTAKA, SUEWAKA, RYOTA, YOSHINO, SHIRO, SADOHARA, SHINYA
• Format: Patent
• Language: English; French; Japanese
• Published: 05.10.2006
• 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; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; 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; TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION; TECHNICAL SUBJECTS COVERED BY FORMER USPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS; UNIDIRECTIONAL SOLIDIFICATION OF EUTECTIC MATERIAL ORUNIDIRECTIONAL DEMIXING OF EUTECTOID MATERIAL

A method of stabilizing the quality of annealed wafer through surely reducing of SSD while ensuring formation of BMD as a gettering source in bulk and decrease of void defects other than SSD on wafer surface that are absolutely essential for annealed wafer. Assuming that annealing of silicon wafer would lead to an increase of density (quantity) of precipitates associated with nitrogen and oxygen becoming SSD nuclei, SSD is reduced through reducing of the density (quantity) of precipitates associated with nitrogen and oxygen by controlling three parameters of oxygen concentration, nitrogen concentration and cooling concentration during the process of pulling-up growth of silicon single-crystal (6) before annealing. Alternatively, SSD is reduced by polishing after annealing. La présente invention concerne un procédé de stabilisation de la qualité d'une plaquette recuite, par la réduction fiable du SSD tout en garantissant la formation de BMD en tant que source d'absorption de gaz en volume et la diminution des défauts de type vides, autres que SSD, sur la surface de la plaquette, absolument essentiels pour une plaquette recuite. En supposant que le recuit de la plaquette de silicium entraînerait une augmentation de la densité (quantité) des précipités associés à de l'azote et de l'oxygène pour former un noyau atomique SSD, on réduit le SSD en diminuant la densité (quantité) des précipités associés à l'azote et l'oxygène en contrôlant trois paramètres, à savoir la concentration de l'oxygène, la concentration de l'azote et la concentration de refroidissement durant le processus de tirage du monocristal de silicium (6) avant le recuit. En variante, on réduit le SSD par polissage après le recuit.