Abstract: An apparatus for producing multicrystalline silicon ingots by the induction method comprises an enclosure, which includes means for start-up heating of silicon and a cooled crucible enveloped by an inductor. The crucible has a movable bottom and four walls consisting of sections spaced apart by vertically extending slots, means for moving the movable bottom, and a controlled cooling compartment arranged under the cooled crucible. The inside face of the crucible defines a melting chamber of a rectangular or square cross-section. The walls of the cooled crucible extend outwards at least from the inductor toward the lowest portion of the cooled crucible to thereby expand the melting chamber, and the angle ? of expanding the melting chamber is defined by the equation ?=arctg[2·(k?1.

Abstract: A lasing medium having a tailored dopant concentration and a method of fabrication thereof is disclosed. The lasing medium has a single crystal having a continuous body having a selected length, wherein the crystal comprises dopant distributed along the length of the body to define a dopant concentration profile. In one embodiment, the dopant concentration profile results in a uniform heating profile. A method of fabricating a laser crystal having a tailored dopant concentration profile includes arranging a plurality of polycrystalline segments together to form an ingot, the polycrystalline segments each having dopant distributed, providing a crystal seed at a first end of the ingot, and moving a heating element along the ingot starting from the first end to a second end of the ingot, the moving heating element creating a moving molten region within the ingot while passing therealong.

Abstract: A silicon single crystal is produced by a method wherein a silicon plate is inductively heated; granular silicon is melted on the silicon plate; and the molten silicon thus produced flows through a flow conduit in the center of the plate to a phase boundary at which a silicon single crystal crystallizes, wherein a silicon ring having a lower resistivity than the plate, and lying on the plate, is inductively heated prior to inductively heating the plate, and melting the ring.

Abstract: Single crystals are produced by means of the floating zone method, wherein the single crystal crystallizes below a melt zone at a crystallization boundary, and the emission of crystallization heat is impeded by a reflector surrounding the single crystal, wherein the single crystal is heated in the region of an outer edge of the crystallization boundary by means of a heating device in a first zone, wherein a distance ? between an outer triple point Ta at the outer edge of the crystallization boundary and a center Z of the crystallization boundary is influenced. An apparatus for producing the single crystal provides a heat source below the melting induction coil and above the reflector.

Abstract: A temperature gradient is established in a crystallization crucible by means of a heat source and a cooling system. The cooling system comprises a heat exchanger and an adjustable additional heat source. The cooling system is preferably formed by an induction coil cooled by a coolant liquid circulating in the induction coil and by an electrically conductive induction susceptor positioned between the crucible and induction coil. The fabrication process comprises heating the crucible via the top and controlling heat extraction from the crucible downwards by means of the heat exchanger and by means of regulation of the adjustable additional heat source.

Abstract: A method for producing thin silicon rods using a floating zone crystallization process includes supplying high frequency (HF) current to a flat induction coil having a central opening, a plurality of draw openings and a plate with a slot as a current supply of the HF current so as to provide a circumfluent current to the central opening. An upper end of a raw silicon rod is heated by induction using the flat induction coil so as to form a melt pool. A thin silicon rod is drawn upwards through each of the plurality of draw openings in the flat induction coil from the melt pool without drawing a thin silicon rod through the central opening having the circumfluent current.

Abstract: The invention provides an apparatus for producing a single crystal, and a method for producing a silicon single crystal using the same. An apparatus for producing a single crystal includes a heating device which heats polycrystalline silicon raw material held in a crucible to form silicon melt, and a pulling up device which grows a silicon single crystal while pulling it up from the silicon melt accompanied with rotation. By providing the apparatus with a magnetic field generation unit which applies to the silicon melt a cusp magnetic field a shape of neutral plane of which is symmetric around the rotation axis of the silicon single crystal and is curved in the upward direction, various conditions for producing a silicon single crystal having a defect free region is relaxed, and a silicon single crystal having a defect free region is produced at high efficiency.

Abstract: An apparatus is provided for manufacturing a single crystal rod from a poly crystal feed rod including a closed chamber at which chamber the feed rod is located. The chamber has an annular energy supply arranged around the feed rod for melting off the one end of the rod for providing single crystals. Actuators are provided, for axial movement of the feed rod and for a rotating relative movement between the feed rod and the annular energy supply The apparatus further includes components for recording and regulating the distance between the surface of the feed rod and an annular inwardly radially facing reference face associated with the energy supply The resulting apparatus and method that enable use of irregular feed rods that assume other shapes than the optimal cylindrical shape and also enable use of curved cylindrical and elliptical rods with irregular surfaces.

Abstract: A doped semiconductor wafer of float zone-pulled semiconductor material contains a dopant added to a molten material and has a radial macroscopic resistance distribution of less than 12% and striations of ?10% to +10%. There is also a process for producing a doped semiconductor wafer by float zone pulling of a single crystal and dividing up the single crystal, in which process, during the float zone pulling, a molten material which is produced using an induction coil is doped with a dopant. It is exposed to at least one rotating magnetic field and is solidified. The single crystal which is formed during the solidification of the molten material is rotated. The single crystal and the magnetic field are rotated with opposite directions of rotation and the magnetic field has a frequency of 400 to 700 Hz.

Abstract: A manufacturing method of a Ga2-xFexO3 crystal is provided which can form a superior, uniform, and large crystal. By a floating zone melting method in which ends of material bars (3, 5), which are disposed at an upper and a lower position and which are composed of Ga2-xFexO3, are heated in a gas atmosphere with halogen lamps (6, 7) disposed at confocal areas so as to form a floating melting zone between the ends of the material bars (3, 5) which are disposed at the upper and the lower position and which are composed of Ga2-xFexO3, Ga2-xFexO3 a single crystal having an orthorhombic crystal structure is formed.

Abstract: The method of protectively coating metallic uranium which comprises dipping the metallic uranium in a molten alloy comprising about 20-75% of copper and about 80-25% of tin, dipping the coated uranium promptly into molten tin, withdrawing it from the molten tin and removing excess molten metal, thereupon dipping it into a molten metal bath comprising aluminum until it is coated with this metal, then promptly withdrawing it from the bath.

Abstract: A feed rod for growing a magnetic single crystal having a composition represented by the formula (Y3-aAa)(Fe5-b-cBb)O12-&agr;, wherein A is at least one element selected from the lanthanoide series, B is at least one element selected from the group consisting of Ga, Al, In, and Sc, c is a value for decreasing the Fe content from the stoichiometric amount, &agr; is a value for decreasing the oxygen content to satisfy the chemically neutral condition, and the relationships 0≦a≧0.5; 0≦b≧1.0; 0<c≧0.15 and 0<&agr; are satisfied.

Abstract: A process produces a crystal of a material with non-congruent melting using at least one first element and a second element. The process includes (a) placing, in a vertical alignment and maintaining under a controlled atmosphere, a bar of the first element gripped between a lower bar and an upper bar made out of the material, (b) transforming the bar of the first element into a floating zone by heating to a temperature that avoids the evaporation of the first element, the heating being obtained by heating means that provides a temperature gradient in the floating zone so that the lower face of the upper bar appears as a cold face, and (c) contra-rotating the lower and upper bars around the alignment axis and moving the whole bar assembly upwards in relation to the heating means in order to obtain the crystal on the cold face by growth in solution.

Abstract: A rotational directional solidification crystal growth system includes a vertical furnace, a crucible, and a rotate support device. The vertical furnace contains a high-temperature portion and a low-temperature portion. The crucible has a seed well and a growth region. The seed well and the growth region contain a seed crystal and raw material, respectively. The crucible moves from the high-temperature portion of the furnace to the low-temperature portion of the furnace or the thermal profile moves related to a stationary crucible to proceed the crystal growth. The rotation support device supports and rotates the crucible, and the tangent velocity of the rotated crucible is no less than about 5&pgr;/3 cm/s.

Abstract: A single crystal producing method for growing a single crystal, comprises the steps of: placing a material at one focal point in a light-condensing and heating furnace having an ellipse in section; placing a heat light source at another focal point; and emitting a laser beam has a wavelength of not less than about 160 nm and not greater than about 1,000 nm, on or near the one focal point to form a melt zone; and moving the melt zone to grow a single crystal.

Abstract: A method and apparatus for locally and successively melting a material by induction heating using a horizontal floating-zone crucible to refine and/or analyze the material. An electromagnetic field is generated to create a localized molten zone within the material that is at least partially levitated within the crucible. The crucible has an upper peripheral opening so that an upper portion of the molten zone is generally at a higher temperature than the lower portion of the molten zone adjacent the crucible wall. As a result, insoluble inclusions within the material separate and float to the upper portion of the molten zone. The molten zone may be translated longitudinally through the material to drive the inclusions toward one end of the material. The process can be carried out to refine or characterize the material, or to determine the solidus and liquidus temperatures of the material.

Abstract: A method for growing a single crystal by allowing a seed crystal to contact a molten zone formed by melting a polycrystalline material, followed by moving the molten zone away from the seed, wherein the oxygen concentration in the atmosphere during growth of the single crystal is lower than about 10% by volume.

Abstract: There is provided a single crystal growth method which allows single crystal of an incongruent melting compound to be grown stable while controlling its growth orientation. The single crystal growth method comprises the steps of: holding polycrystal and seed crystal within a heating furnace; joining the polycrystal with the seed crystal; heating the polycrystal on the side opposite from the side where the polycrystal is joined with the seed crystal to form a melt zone; moving the melt zone to the side where the polycrystal is joined with the seed crystal so that the melt zone is in contact with the seed crystal to allow seeding; and growing single crystal by moving the melt zone which has been in contact with the seed crystal and been seeded to the opposite side from the side where the polycrystal is joined with the seed crystal.

Abstract: A high-frequency induction heater for use in the growth of a semiconductor single crystal by the FZ method, including a plurality of high-frequency induction heating coils disposed in concentric juxtaposed relation to each other and each having a pair of power supply terminals provided for supplying a high-frequency current to the associated heating coil, with the power supply terminals of one of the heating coils being disposed in a space defined between opposite ends of an adjacent heating coil disposed outside the one heating coil, wherein a pair of electrically conductive members is attached to the pair of power supply terminals, respectively, of at least an innermost one of the heating coils so as to cover a space defined between the power supply terminals of the innermost heating coil. With the induction heater thus constructed, the so-called "pulsation", i.e.

Abstract: A method of producing a silicon single crystal by the floating-zone method, comprising the steps of: providing a polysilicon rod having an average grain length of 10 to 1000 .mu.m; heating a portion of the polysilicon rod to form a molten zone while applying a magnetic field of 300 to 1000 gauss to the molten zone; and passing the molten zone through the length of the polysilicon rod thereby the polysilicon rod is converted into a silicon single crystal ingot through a one-pass zoning of the floating zone method. An apparatus for reducing the method into practice is also described. The growing single crystal ingot is post-heated by a heat reflector near the molten zone.

Abstract: A polycrystalline silicon rod for preparing a monocrystalline silicon rod by a floating zone method, wherein at least a central portion of the section of the polycrystalline silicon rod has coarsened silicon monocrystalline grains around the center over an area of or above the minimum section of a molten zone during progress in the floating zone method and the outer peripheral portion of the coarsened region has fine monocrystalline grains. From the polycrystalline silicon rod, the monocrystalline silicon rod for a semiconductor is prepared with a high yield by the single floating zone method.