In a process for producing a silicon single crystal in which carbon is incorporated in order to inhibit crystal defects, provided is a process which easily allows carbon to be mixed and dissolved into a silicon melt. The process for producing a silicon single crystal, which involves allowing a silicon single crystal to grow during its pulling-up from the silicon melt held in a crucible, uses as at least part of a silicon raw material, crushed materials of a polycrystalline silicon rod produced by Siemens process that are obtained by crushing an end of the rod in the vicinity contacting a carbon core wire holding member.

A single-crystal silicon carbide and a single-crystal silicon carbide wafer of good-quality are disclosed that are low in dislocations, micropipes and other crystal defects and enable high yield and high performance when applied to a device, wherein the ratio of doping element concentrations on opposite sides in the direction of crystal growth of the interface between the seed crystal and the grown crystal is 5 or less and the doping element concentration of the grown crystal in the vicinity of the seed crystal is 2×10.sup.19 cm.sup.−3 to 6×10.sup.20 cm.sup.−3.

A single-crystal silicon carbide and a single-crystal silicon carbide wafer of good-quality are disclosed that are low in dislocations, micropipes and other crystal defects and enable high yield and high performance when applied to a device, wherein the ratio of doping element concentrations on opposite sides in the direction of crystal growth of the interface between the seed crystal and the grown crystal is 5 or less and the doping element concentration of the grown crystal in the vicinity of the seed crystal is 2×10.sup.19 cm.sup.−3 to 6×10.sup.20 cm.sup.−3.

A biomedical implant (16, 18) is formed from magnesium (Mg) single crystal (10). The biomedical implant (16, 18) may be biodegradable. The biomedical implant (16, 18) may be post treated to control the mechanical properties and/or corrosion rate thereof said Mg single crystal (10) without changing the chemical composition thereof. A method of making a Mg single crystal (10) for biomedical applications includes filling a single crucible (12) with more than one chamber with polycrystalline Mg, melting at least a portion of said polycrystalline Mg, and forming more than one Mg single crystal (10) using directional solidification.

The disclosure describes multilayer hard magnetic materials including at least one layer including α″-Fe.sub.16N.sub.2 and at least one layer including α″-Fe.sub.16(N.sub.xZ.sub.1-x).sub.2 or a mixture of α″-Fe.sub.16N.sub.2 and α″-Fe.sub.16Z.sub.2, where Z includes at least one of C, B, or O, and x is a number greater than zero and less than one. The disclosure also describes techniques for forming multilayer hard magnetic materials including at least one layer including α″-Fe.sub.16N.sub.2 and at least one layer including α″-Fe.sub.16(N.sub.xZ.sub.1-x).sub.2 or a mixture of α″-Fe.sub.16N.sub.2 and α″-Fe.sub.16Z.sub.2 using chemical vapor deposition or liquid phase epitaxy.

A method for producing an array or bed of metallic nanotubes includes formation of nanowires made from sacrificial material on a growth support, deposition of a metal layer on the nanowires so as to form metallic nanotubes concentric with the nanowires, deposition of a polymer binding layer between the nanowires, elimination of the support, the binding layer supporting the metallic nanotubes, and etching of the sacrificial material.

A method for producing an array or bed of metallic nanotubes includes formation of nanowires made from sacrificial material on a growth support, deposition of a metal layer on the nanowires so as to form metallic nanotubes concentric with the nanowires, deposition of a polymer binding layer between the nanowires, elimination of the support, the binding layer supporting the metallic nanotubes, and etching of the sacrificial material.

Single-crystal diamond is composed of carbon in which a concentration of a carbon isotope .sup.12C is not lower than 99.9 mass % and a plurality of inevitable impurities other than carbon. The inevitable impurities include nitrogen, boron, hydrogen, and nickel, and a total content of nitrogen, boron, and hydrogen of the plurality of inevitable impurities is not higher than 0.01 mass %. In order to manufacture single-crystal diamond, initially, a hydrocarbon gas in which a concentration of the carbon isotope .sup.12C is not lower than 99.9 mass % is subjected to denitrification.

Single-crystal diamond is composed of carbon in which a concentration of a carbon isotope .sup.12C is not lower than 99.9 mass % and a plurality of inevitable impurities other than carbon. The inevitable impurities include nitrogen, boron, hydrogen, and nickel, and a total content of nitrogen, boron, and hydrogen of the plurality of inevitable impurities is not higher than 0.01 mass %. In order to manufacture single-crystal diamond, initially, a hydrocarbon gas in which a concentration of the carbon isotope .sup.12C is not lower than 99.9 mass % is subjected to denitrification.

A system and method for fabricating a perovskite film is provided, the system including a housing for use as a CVD furnace having first and second sections coupled with first and second temperature control units, respectively. The first and second sections correspond substantially to the upstream and downstream of gases, respectively. One or more substrates are loaded in the second section and controlled by the second temperature control unit, and an evaporation unit containing an organic halide material is loaded in the first section and controlled by the first temperature control unit. Each of the substrates is pre-deposited with a metal halide material. The inside of the housing is pumped down to a low pressure.