Methods Apparatus for Manufacturing Geometric Multi-Crystalline Cast Materials

Abstract

Methods are provided for casting one or more of a semi-conductor, an oxide, and an intermetallic material. With such methods, a cast body of a geometrically ordered multi-crystalline form of the one or more of a semiconductor, an oxide, and an intermetallic material may be formed that is free or substantially free of radially-distributed impurities and defects and having at least two dimensions that are each at least about 10 cm.

What is claimed: 
     
         1 . A method of casting one or more of a semiconductor, an oxide, and an intermetallic material, comprising:
 placing a geometric arrangement of a plurality of monocrystalline seed crystals on at least one surface in a crucible having one or more side walls heated to at least the melting temperature of the one or more materials, and at least one wall for cooling;   placing a molten form of the one or more materials in contact with the geometric arrangement of monocrystalline seed crystals; and   forming a solid body comprising a geometrically ordered multi-crystalline form of the one or more materials, optionally having at least two dimensions each being at least about 10 cm, by cooling the molten form of the one or more materials to control crystallization, wherein the forming includes controlling a solid-liquid interface at an edge of the molten form of the one or more materials during the cooling so as to move in a direction that increases a distance between the molten form of the one or more materials and the at least one wall for cooling,   wherein the cooling includes using a heat sink material for radiating heat to water-cooled walls.   
     
     
         2 . The method according to any one of  claim 1 , comprising forming a portion of the solid body to include the plurality of seed crystals. 
     
     
         3 . The method according to  claim 1 , wherein the placing the molten form of the one or more materials further includes melting feedstock of the one or more materials in a melt container separate from the crucible, heating the crucible and the one or more materials to the melting temperature of the one or more materials, controlling the heating so that the plurality of seed crystals in the crucible does not melt completely, and transferring the molten form of the one or more materials from the melt container into the crucible. 
     
     
         4 . The method according to  claim 1 , comprising arranging the plurality of seed crystals so that a common pole direction among the seed crystals is perpendicular to a bottom of the crucible. 
     
     
         5 . The method according to  claim 1 , wherein the forming comprises forming a geometrically ordered multi-crystalline form of the one or more materials having an average grain size of about 0.5 cm to about 50 cm so that a common pole direction is perpendicular to the surface of the geometrically ordered multi-crystalline form of the one or more materials. 
     
     
         6 . The method according to  claim 1 , comprising forming another solid body of a geometrically ordered multi-crystalline form of the one or more materials using a seed crystal obtained from a body of a continuous geometrically ordered multi-crystalline form of the one or more materials previously cast according to said method. 
     
     
         7 . The method according to  claim 1 , comprising arranging the plurality of seed crystals so that a common pole direction among the seed crystals is perpendicular to one of the at least two surfaces of the crucible so that no grain boundaries are formed between the at least two surfaces of the crucible. 
     
     
         8 . The method according to  claim 1 , comprising arranging the plurality of seed crystals so that a maximum of three seed crystal edges meet at any corner of the predetermined pattern. 
     
     
         9 . The method according to  claim 1 , wherein placing the geometric arrangement of a plurality of monocrystalline seed crystals comprises arranging the seed crystals to cover an entire or substantially an entire area of a surface of the crucible. 
     
     
         10 . A body of one or more of a semiconductor, an oxide, and an intermetallic material, made according to the method claim. 
     
     
         11 . The method according to  claim 1 , wherein the at least one seed crystal or plurality of seed crystals comprises a geometric multi-crystalline form one or more of a semiconductor, an oxide, and an intermetallic material. 
     
     
         12 . The method according to  claim 1 , wherein one or more of a semiconductor, an oxide, and an intermetallic material is selected from the group consisting of germanium, gallium arsenide, silicon germanium, aluminum oxide, sapphire, gallium nitride, zinc oxide, zinc sulfide, gallium indium arsenide, indium antimonide, germanium yttrium barium oxides, lanthanide oxides, magnesium oxide, and calcium oxide.