A rare earth thin-film magnet of a Nd—Fe—B film deposited on a Si substrate, wherein, when the film thickness of the rare earth thin film is 70 μm or less, the Nd content satisfies the conditional expression of 0.15≦Nd/(Nd+Fe)≦0.25 in terms of an atomic ratio; when the film thickness of the rare earth thin film is 70 μm to 115 μm (but excluding 70 μm), the Nd content satisfies the conditional expression of 0.18≦Nd/(Nd+Fe)≦0.25 in terms of an atomic ratio; and when the film thickness of the rare earth thin film is 115 μm to 160 μm (but excluding 115 μm), the Nd content satisfies the conditional expression of 0.20≦Nd/(Nd+Fe)≦0.25 in terms of an atomic ratio. An object of the present invention is to provide a rare earth thin-film magnet having a maximum film thickness of 160 μm and which is free from film separation and substrate fracture, and a method of producing such a rare earth thin-film magnet by which the thin film can be stably deposited.

The present invention provides a rare earth thin film magnet having Nd, Fe, and B as essential components, wherein the rare earth thin film magnet has a texture in which an α-Fe phase and a Nd.sub.2Fe.sub.14B phase are alternately arranged three-dimensionally, and each phase has an average crystal grain size of 10 to 30 nm. An object of this invention is to provide a rare earth thin film magnet having superior mass productivity and reproducibility and favorable magnetic properties, as well as to provide the production method thereof and a target for producing the thin film.

A magnetic material is constituted of a ferromagnetic or ferrimagnetic insulator in a double perovskite structure of Sr.sub.3-xA.sub.xOs.sub.1-yB.sub.yO.sub.6 (0.5≤x≤0.5, −0.5≤y≤0.5). A is an alkali metal or alkaline earth metal atom, and B is a transition metal atom, alkali metal atom, or alkaline earth metal atom). The insulator may be Sr.sub.3OsO.sub.6, where x=y=0 in the above formula. Sr.sub.3OsO.sub.6 is formed to have a cubic crystal structure where strontium atoms, osmium atoms, and oxygen atoms are arranged at lattice points.

A rare-earth thin film magnet is provided which includes Nd, Fe and B as essential components, characterized by including a Si substrate having an oxide film present on a surface thereof, a Nd base film formed as a first layer over the Si substrate, and a Nd—Fe—B film formed as a second layer on the first layer. The rare earth thin film magnet and a production process therefor provides a rare earth thin film magnet suffering neither film separation nor substrate breakage and having satisfactory magnetic properties even when the second layer has composition in the range of 0.120 ≤Nd/(Nd+Fe)<0.150, which corresponds to a compositional range in the vicinity of a stoichiometric composition.

Provided is a rare earth thin film magnet having Nd, Fe and B as essential components, which is characterized in that a Nd—Fe—B base film is formed on a Si substrate having an oxide film formed on a surface thereof and has a composition in which the Nd content is higher than that of a stoichiometric composition and that a film (nano composite film) is formed on the base film and has a texture in which an α-Fe phase and Nd.sub.2Fe.sub.14B are alternately arranged and three-dimensionally dispersed. The rare earth thin film magnet provided is less susceptible to the occurrence of film separation and substrate breakage and exhibits favorable magnetic properties.

A magnetic material is constituted of a ferromagnetic or ferrimagnetic insulator in a double perovskite structure of Sr.sub.3-xA.sub.xOs.sub.1-yB.sub.yO.sub.6 (0.5x0.5, 0.5y0.5). A is an alkali metal or alkaline earth metal atom, and B is a transition metal atom, alkali metal atom, or alkaline earth metal atom). The insulator may be Sr.sub.3OsO.sub.6, where x=y=0 in the above formula. Sr.sub.3OsO.sub.6 is formed to have a cubic crystal structure where strontium atoms, osmium atoms, and oxygen atoms are arranged at lattice points.

A method of making a ferrite thin film is provided in which a portion of the iron ions in the ferrite are substituted by ions of at least one other metal. The substituting ions occupy both tetrahedral and octahedral sites in the unit cell of the ferrite crystal. The method includes placing each of a plurality of targets, one at a time, in close proximity to a substrate in a defined sequence; ablating the target thus placed using laser pulses, thereby causing ions from the target to deposit on the substrate; repeating these steps, thereby generating a film; and annealing the film in the presence of oxygen. The plurality of targets, the sequence of their ablation, and the number of laser pulses that each target is subjected to, are selected so as to allow the substituting ions to occupy both tetrahedral and octahedral sites in the unit cell.

A rare-earth thin film magnet is provided which includes Nd, Fe and B as essential components, characterized by including a Si substrate having an oxide film present on a surface thereof, a Nd base film formed as a first layer over the Si substrate, and a NdFeB film formed as a second layer on the first layer. The rare earth thin film magnet and a production process therefor provides a rare earth thin film magnet suffering neither film separation nor substrate breakage and having satisfactory magnetic properties even when the second layer has composition in the range of 0.120 5 Nd/(Nd+Fe)<0.150, which corresponds to a compositional range in the vicinity of a stoichiometric composition.

A rare earth thin-film magnet of a NdFeB film deposited on a Si substrate, wherein, when the film thickness of the rare earth thin film is 70 m or less, the Nd content satisfies the conditional expression of 0.15Nd/(Nd+Fe)0.25 in terms of an atomic ratio; when the film thickness of the rare earth thin film is 70 m to 115 m (but excluding 70 m), the Nd content satisfies the conditional expression of 0.18Nd/(Nd+Fe)0.25 in terms of an atomic ratio; and when the film thickness of the rare earth thin film is 115 m to 160 m (but excluding 115 m), the Nd content satisfies the conditional expression of 0.20Nd/(Nd+Fe)0.25 in terms of an atomic ratio. An object of the present invention is to provide a rare earth thin-film magnet having a maximum film thickness of 160 m and which is free from film separation and substrate fracture, and a method of producing such a rare earth thin-film magnet by which the thin film can be stably deposited.

A single-crystalline LnBM.sub.2O.sub.5+ or LnBM.sub.2O.sub.5.5+ compound is provided, which includes an ordered oxygen vacancy structure; wherein Ln is a lanthanide, B is an alkali earth metal, M is a transition metal, O is oxygen, and 01. Methods of making and using the compound, and devices and compositions including same are also provided.