MAGNESIUM OXIDE SINGLE CRYSTAL AND METHOD FOR PRODUCING SAME

• Main Authors: KAWAGUCHI, YOSHIFUMI, TOUTSUKA, ATSUO, KUNISHIGE, MASAAKI
• 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; CHEMICAL SURFACE TREATMENT; CHEMISTRY; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATIONOR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY IONIMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; COATING MATERIAL WITH METALLIC MATERIAL; COATING METALLIC MATERIAL; COMPOUNDS OF THE METALS BERYLLIUM, MAGNESIUM, ALUMINIUM,CALCIUM, STRONTIUM, BARIUM, RADIUM, THORIUM, OR OF THERARE-EARTH METALS; CRYSTAL GROWTH; DIFFUSION TREATMENT OF METALLIC MATERIAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION INGENERAL; INORGANIC CHEMISTRY; 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; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THESURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; UNIDIRECTIONAL SOLIDIFICATION OF EUTECTIC MATERIAL ORUNIDIRECTIONAL DEMIXING OF EUTECTOID MATERIAL

Disclosed are an MgO single crystal which enables to obtain a magnesium oxide (MgO) single crystal vapor-deposited material which is prevented from occurrence of splashing without decreasing the film-forming rate during vapor deposition by a electron beam deposition method or the like; and an MgO single crystal which enables to obtain an MgO single crystal substrate capable of forming, for example, a superconducting thin film having excellent superconducting characteristics. Specifically disclosed is an MgO single crystal having a calcium content of from 150 × 10-6 to 1000 × 10-6 kg/kg and a silicon content of 10 × 10-6 kg/kg or less, wherein the variation of the detected amount of calcium fragment ions is 30 % or less in terms of the CV value when a polished surface of the MgO single crystal is analyzed by the TOF-SIMS. Also specifically disclosed are an MgO single crystal vapor-deposited material and an MgO single crystal substrate for forming a thin film which are obtained from such an MgO single crystal. La présente invention propose un monocristal de MgO qui permet d'obtenir un matériau de monocristal d'oxyde de magnésium (MgO) déposé en phase vapeur, les éclaboussures étant évitées sans diminution du taux de formation du film durant le dépôt en phase vapeur par un procédé de dépôt par faisceau d'électrons ou par un procédé semblable, et un monocristal de MgO qui permet d'obtenir un substrat de monocristal de MgO capable de former, par exemple, un film mince super-conducteur ayant d'excellentes caractéristiques de super-conduction. Spécifiquement, l'invention propose un monocristal de MgO ayant une teneur en calcium comprise entre 150 × 10-6 et 1000 × 10-6 kg/kg et une teneur en silicium inférieure ou égale à 10 × 10-6 kg/kg, la variation de la quantité détectée de fragments d'ions calcium étant inférieure ou égale à 30 % en termes de la valeur CV lorsqu'une surface polie du monocristal de MgO est analysée par TOF-SIMS. L'invention divulgue également spécifiquement un matériau de monocristal de MgO déposé en phase vapeur et un substrat de monocristal de MgO qui sont destinés à former un film mince et qui sont obtenus à partir d'un monocristal de MgO.