PROCÉDÉ PERMETTANT DE FAIRE POUSSER UN CRISTAL UNIQUE DE SILICIUM ET PROCESSUS POUR PRODUIRE UNE TRANCHE DE SILICIUM
| N° de brevet: |
EP1895027 (A1) |
| Date de publication: |
2008-03-05 |
| Inventeur(s): |
KOGURE YASUHIRO [JP];TAKASE NOBUMITSU [JP];INAMI SHUICHI [JP];NAKAMURA TSUYOSHI [JP];HAMADA KEN [JP]; |
| Demandeur(s): |
SUMCO CORP [JP]; |
| Classification: |
C30B29/06;C30B15/20; |
| N° de demande: |
EP20050806144 20051108 |
| Numéro(s) de priorité: |
WO2005JP20434 20051108;JP20050179997 20050620 |
In a method for growing a silicon single crystal, a silicon single crystal is grown by the Czochralski method to have an oxygen concentration of 12&dlowbar;10 17 to 18&dlowbar;10 17 atoms/cm 3 on ASTM-F 121 1979. A mixed gas of an inert gas and a gaseous substance containing hydrogen atoms is used as an atmospheric gas for growing the single crystal. A temperature of the silicon single crystal is controlled during the growth of the crystal such that the ratio Gc/Ge of an axial thermal gradient Gc at the central portion of the crystal between its melting point and its temperature of 1350°C to an axial thermal gradient Ge at the periphery of the crystal between its melting point and its temperature of 1350°C is 1.1 to 1.4. The axial thermal gradient Gc at the central portion of the crystal is 3.0 to 3.5°C/mm.
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