Abstract: A SiC single crystal is produced by impregnating a molten alloy of silicon and a metallic element M that increases carbon solubility into a SiC sintered body to form a SiC crucible, placing silicon and M in the crucible and heating the crucible to melt the silicon and M and form a Si—C solution, dissolving silicon and carbon in the solution from surfaces of the crucible in contact with the solution, contacting a SiC seed crystal with the top of the solution to grow a first SiC single crystal on the SiC seed crystal by a solution process, and bulk growing a second SiC single crystal on a face of the solution-grown first SiC single crystal by a sublimation or gas process. This method enables a low-dislocation, high-quality SiC single crystal to be produced by a vapor phase process.

Abstract: In SiC single crystal production by the solution process, an alloy of silicon (Si) and a metallic element M that increases the solubility of carbon (C) is pre-impregnated into a SiC sintered body having a relative density of 50 to 90%, following which Si and M are placed in a SiC crucible made of the SiC sintered body and the Si and M within the SiC crucible are melted, forming a Si—C solution. With heating, SiC from the SiC sintered body dissolves into the Si—C solution, efficiently supplying Si and C to the Si—C solution. As a result, Si and C are supplied uniformly and in the proper amount from all areas of contact between the SiC crucible and the Si—C solution, enabling a high-quality SiC single crystal to be stably produced over a long time at a rapid growth rate.

Abstract: In the present invention, in producing a SiC single crystal in accordance with a solution method, a crucible containing SiC as a main component and having an oxygen content of 100 ppm or less is used as the crucible to be used as a container for a Si—C solution. In another embodiment, a sintered body containing SiC as a main component and having an oxygen content of 100 ppm or less is placed in the crucible to be used as a container for a Si—C solution. The SiC crucible and SiC sintered body are obtained by molding and baking a SiC raw-material powder having an oxygen content of 2000 ppm or less. SiC, which is the main component of these, serves as a source for Si and C and allows Si and C to elute into the Si—C solution by heating.

Abstract: A SiC single crystal is prepared by the solution process of placing a seed crystal in contact with a Si—C solution in a crucible and letting a SiC single crystal to grow from the seed crystal. The method includes the first growth step of conducting crystal growth using (0001) or (000-1) plane of a SiC single crystal of which the seed crystal is composed, as the growth surface, and the second growth step of conducting crystal growth using (1-100) or (11-20) plane of a SiC single crystal resulting from the first growth step as the growth surface. A SiC single crystal of high homogeneity and quality is obtained, which is reduced in threading screw dislocations, threading edge dislocations, basal plane dislocations, micropipes, and stacking faults.

Abstract: A SiC single crystal is prepared by the solution process of placing a seed crystal in contact with a Si-C solution in a crucible and letting a SiC single crystal to grow from the seed crystal. The method includes the first growth step of conducting crystal growth using (0001) or (000-1) plane of a SiC single crystal of which the seed crystal is composed, as the growth surface, and the second growth step of conducting crystal growth using (1-100) or (11-20) plane of a SiC single crystal resulting from the first growth step as the growth surface. A SiC single crystal of high homogeneity and quality is obtained, which is reduced in threading screw dislocations, threading edge dislocations, basal plane dislocations, micropipes, and stacking faults.

Abstract: In the present invention, in producing a SiC single crystal in accordance with a solution method, a crucible containing SiC as a main component and having an oxygen content of 100 ppm or less is used as the crucible to be used as a container for a Si—C solution. In another embodiment, a sintered body containing SiC as a main component and having an oxygen content of 100 ppm or less is placed in the crucible to be used as a container for a Si—C solution. The SiC crucible and SiC sintered body are obtained by molding and baking a SiC raw-material powder having an oxygen content of 2000 ppm or less. SiC, which is the main component of these, serves as a source for Si and C and allows Si and C to elute into the Si—C solution by heating.

Abstract: In the present invention, in producing a SiC single crystal in accordance with a solution method, a crucible containing SiC as a main component and having an oxygen content of 100 ppm or less is used as the crucible to be used as a container for a Si—C solution. In another embodiment, a sintered body containing SiC as a main component and having an oxygen content of 100 ppm or less is placed in the crucible to be used as a container for a Si—C solution. SiC, which is the main component of these, serves as a source for Si and C and allows Si and C to elute into the Si—C solution by heating. Since the oxygen content of SiC is 100 ppm or less, generation of gas in the Si—C solution is suppressed.

Abstract: In the present invention, a crucible formed of SiC as a main component is used as a container for a Si—C solution. A metal element M (M is at least one metal element selected from at least one of a first group consisting of La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho and Lu, a second group consisting of Ti, V, Cr, Mn, Fe, Co, Ni and Cu and a third group consisting of Al, Ga, Ge, Sn, Pb and Zn) is added to the Si—C solution and the crucible is heated to elute Si and C, which are derived from a main component SiC of the crucible, from a high-temperature surface region of the crucible in contact with the Si—C solution, into the Si—C solution. In this way, precipitation of a SiC polycrystal on a surface of the crucible in contact with the Si—C solution is suppressed.

Abstract: In the present invention, a crucible formed of SiC as a main component is used as a container for a Si—C solution. The SiC crucible is heated such that, for example, an isothermal line representing a temperature distribution within the crucible draws an inverted convex shape; and Si and C, which are derived from a main component SiC of the crucible, are eluted from a high-temperature surface region of the crucible in contact with the Si—C solution, into the Si—C solution, thereby suppressing precipitation of a SiC polycrystal on a surface of the crucible in contact with the Si—C solution. To the Si—C solution of this state, a SiC seed crystal is moved down from the upper portion of the crucible closer to the Si—C solution and brought into contact with the Si—C solution to grow a SiC single crystal on the SiC seed crystal.

Abstract: In the present invention, a crucible formed of SiC as a main component is used as a container for a Si—C solution. The SiC crucible is heated such that, for example, an isothermal line representing a temperature distribution within the crucible draws an inverted convex shape; and Si and C, which are derived from a main component SiC of the crucible, are eluted from a high-temperature surface region of the crucible in contact with the Si—C solution, into the Si—C solution, thereby suppressing precipitation of a SiC polycrystal on a surface of the crucible in contact with the Si—C solution. To the Si—C solution of this state, a SiC seed crystal is moved down from the upper portion of the crucible closer to the Si—C solution and brought into contact with the Si—C solution to grow a SiC single crystal on the SiC seed crystal.

Abstract: In the present invention, a crucible formed of SiC as a main component is used as a container for a Si—C solution. A metal element M (M is at least one metal element selected from at least one of a first group consisting of La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho and Lu, a second group consisting of Ti, V, Cr, Mn, Fe, Co, Ni and Cu and a third group consisting of Al, Ga, Ge, Sn, Pb and Zn) is added to the Si—C solution and the crucible is heated to elute Si and C, which are derived from a main component SiC of the crucible, from a high-temperature surface region of the crucible in contact with the Si—C solution, into the Si—C solution. In this way, precipitation of a SiC polycrystal on a surface of the crucible in contact with the Si—C solution is suppressed.

Abstract: A negative electrode material is provided for lithium ion batteries offering a high capacity and a long cycle life. It is an alloy material consisting essentially of Si, Al, M1, and M2 wherein M1 is a transition metal, and M2 is a metal element of Groups 4 and 5, and having an Si—Al-M1-M2 alloy phase constituting fine crystal grains and an Si phase precipitating along crystal grain boundaries to form a network.

Abstract: A complex alloy of at least three phases comprising a composite alloy composed of an Si single phase and an Si—Al-M alloy phase, and an L phase offers a negative electrode material. M is an element selected from transition metals and metals of Groups 4 and 5, and L is In, Sn, Sb, Pb or Mg. The negative electrode material provides a lithium ion battery with a high capacity and long life. The material itself is highly conductive and increases the energy density per volume of a lithium ion battery.

Abstract: Provided is a textured silicon substrate for a magnetic disk, comprising a magnetic film in which magnetic anisotropy can be attained and high recording density can be achieved, while ensuring the flying stability of a head by controlling the surface roughness of the substrate through texturing. Especially, provided is a surface-treated silicon substrate for a magnetic disk, comprising a texture formed on a surface of a silicon substrate comprising an oxide film of 0 to 2 nm thickness, and a magnetic recording medium comprising the surface-treated silicon substrate. Also provided is a method for manufacturing a surface-treated silicon substrate for a magnetic disk, comprising steps of: removing or reducing an oxide film on a surface of a silicon substrate; and forming a texture on the surface of the silicon substrate having the oxide film removed or reduced using a free abrasive-containing slurry and a tape; and a magnetic recording medium comprising the silicon substrate.

Abstract: Provided is a textured silicon substrate for a magnetic disk, comprising a magnetic film in which magnetic anisotropy can be attained and high recording density can be achieved, while ensuring the flying stability of a head by controlling the surface roughness of the substrate through texturing. Especially, provided is a surface-treated silicon substrate for a magnetic disk, comprising a texture formed on a surface of a silicon substrate comprising an oxide film of 0 to 2 nm thickness, and a magnetic recording medium comprising the surface-treated silicon substrate. Also provided is a method for manufacturing a surface-treated silicon substrate for a magnetic disk, comprising steps of: removing or reducing an oxide film on a surface of a silicon substrate; and forming a texture on the surface of the silicon substrate having the oxide film removed or reduced using a free abrasive-containing slurry and a tape; and a magnetic recording medium comprising the silicon substrate.

Abstract: Provided is a surface-treated substrate in which the roughness of the surface of the substrate is controlled. The surface-treated substrate can form a magnetic recording medium in which head flying stability is maintained and which has a magnetic film that can achieve high recording densities. Also provided is a method for roughening the surface of the substrate. More specifically, provided is a surface-treated silicon substrate for a magnetic recording medium in which a surface used for forming a recording layer has 40 to 1000 protrusions per 1 ?m2 with a maximum height of 10 nm or less and an average roughness of 0.3 to 2.0 nm, and in which there are no defects or spots on any of the surface. Furthermore, provided is a method for manufacturing the surface-treated silicon substrate for the magnetic recording medium, comprising a step of etching a surface of a silicon substrate, wherein ultrasound is applied to the surface of the silicon substrate with the substrate shaken or rotated.

Abstract: Provided is a surface-treated substrate in which the roughness of the surface of the substrate is controlled. The surface-treated substrate can form a magnetic recording medium in which head flying stability is maintained and which has a magnetic film that can achieve high recording densities. Also provided is a method for roughening the surface of the substrate. More specifically, provided is a surface-treated silicon substrate for a magnetic recording medium in which a surface used for forming a recording layer has 40 to 1000 protrusions per 1 ?m2 with a maximum height of 10 nm or less and an average roughness of 0.3 to 2.0 nm, and in which there are no defects or spots on any of the surface. Furthermore, provided is a method for manufacturing the surface-treated silicon substrate for the magnetic recording medium, comprising a step of etching a surface of a silicon substrate, wherein ultrasound is applied to the surface of the silicon substrate with the substrate shaken or rotated.

Abstract: Provided is a textured silicon substrate for a magnetic disk, comprising a magnetic film in which magnetic anisotropy can be attained and high recording density can be achieved, while ensuring the flying stability of a head by controlling the surface roughness of the substrate through texturing. Especially, provided is a surface-treated silicon substrate for a magnetic disk, comprising a texture formed on a surface of a silicon substrate comprising an oxide film of 0 to 2 nm thickness, and a magnetic recording medium comprising the surface-treated silicon substrate. Also provided is a method for manufacturing a surface-treated silicon substrate for a magnetic disk, comprising steps of: removing or reducing an oxide film on a surface of a silicon substrate; and forming a texture on the surface of the silicon substrate having the oxide film removed or reduced using a free abrasive-containing slurry and a tape; and a magnetic recording medium comprising the silicon substrate.

Abstract: The polished object is prevented from sticking to the upper polishing mechanism wherein the sticking is a cause for the damages to the polished object and reduction of the yield. There is provided a double side polishing method comprising steps of: inserting an object between a pair of upper and lower polishing mechanisms and polishing the object by rotating or sliding the object therebetween, wherein an adsorption strength of a contact surface of the upper polishing mechanism onto the object is weaker than an adsorption strength of a contact surface of the lower polishing mechanism onto the object.

Abstract: In plating on an Si substrate, it has been strongly demanded to apply a treatment for providing an excellent adhesion so as to resist a post-processing such as polishing and for facilitating plating. Then, provided is a plated substrate adapted for hard disk medium comprising an Si single crystal; an amorphous layer on the substrate, the amorphous layer having thickness of 2 to 200 nm and containing Si and one or more metals selected from a group consisting of Ni, Cu and Ag; a multicrystal layer on the amorphous layer, the multicrystal layer having thickness of 5 to 1000 nm and containing Si and one or more metals selected from a group consisting of Ni, Cu and Ag.