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. 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 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.

Abstract: Provided is a monocrystalline Si substrate on which one or more metal films having good adhesion to the Si monocrystalline substrate are formed so that the adhesion is ensured. More specifically, provided is a surface-treated substrate comprising a monocrystalline Si substrate having volume resistivity of 1 to 100 ?·cm, and at least one metal-plated layer on the monocrystalline Si substrate. The metal-plated layer which faces to the monocrystalline Si substrate preferably comprises at least one metal selected from the group consisting of Ag, Co, Cu, Ni, Pd, Fe and Pt. Furthermore, provided is a perpendicular magnetic recording medium comprising the monocrystalline Si substrate coated with the metal-plated layer.

Abstract: A magnetic recording medium substrate has a diameter of not more than 90 mm and disposed thereon a soft magnetic film plating layer comprising an alloy that comprises at least two metals selected from the group consisting of Co, Ni and Fe. In a concentric circular direction within the substrate plane, a value of the coercive force obtained by a VSM magnetization measurement, is less than 30 oersteds, and a ratio of saturation magnetization to residual magnetization is from 50/1 to 5/1. Spike noise deterioration of signal reproduction caused by leaking magnetic fields is reduced in the soft magnetic layer.

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.

Abstract: Provided are a surface-treated substrate for a magnetic recording medium which has uniform properties with regards to film formation above a non-magnetic substrate and can contain thick film, and the magnetic recoding medium comprising a recording layer. More specifically, it has been found that it is effective that the surface-treated substrate for the magnetic recording medium comprises a non-magnetic substrate and a primer plating layer disposed on the non-magnetic substrate wherein the non-magnetic substrate has been subjected to hydrophilic treatment. It has been also found that a magnetic recording medium comprising the surface-treated substrate for a magnetic recording medium, a soft magnetic layer and a recording layer is preferable as a perpendicular magnetic recording medium.

Abstract: The present invention provides a surface-treated substrate for a magnetic recording medium, and a magnetic recording medium comprising a recording layer, wherein the surface-treated substrate can contain thick film which has adhesion strong enough to withstand leveling process such as polishing in the formation of film on the Si substrate. More specifically, the present invention provides a surface-treated substrate for a magnetic recording medium, comprising a Si substrate and a primer plating layer on the Si substrate, wherein the primer plating layer is film which comprises a metal and a Si oxide. Furthermore, the present invention provides a surface-treated substrate for a magnetic recording medium, comprising a Si substrate and a primer plating layer on the Si substrate, wherein at least 5 and at most 50 protrusions of a height of at least 100 nm per 100 &mgr;m2 are present on a surface of the primer plating layer.

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.