Metal oxides and method for forming the method oxides are provided. The disclosed functional metal oxides are single crystalline or polycrystalline metal oxides, such as, for example, SrVO.sub.3, and have dimensions, phase purity, and crystalline quality previously unachievable. The disclosed methods include a combination of a gas atmosphere, vacuum sintering, and laser-based directional solidification of a seed rod in contact with a feed rod that is scalable for production quantities.

Metal oxides and method for forming the method oxides are provided. The disclosed functional metal oxides are single crystalline or polycrystalline metal oxides, such as, for example, SrVO.sub.3, and have dimensions, phase purity, and crystalline quality previously unachievable. The disclosed methods include a combination of a gas atmosphere, vacuum sintering, and laser-based directional solidification of a seed rod in contact with a feed rod that is scalable for production quantities.

A composite substrate capable of improving temperature characteristics while suppressing crack generation and a method for manufacturing such composite substrate is provided. The method for manufacturing composite substrates includes: a step of preparing a piezoelectric material substrate having a rough surface; a step of removing the damaged layer by etching the rough surface of the piezoelectric material substrate using a chemical process; a step of depositing an intervening layer on the rough surface of the piezoelectric material substrate from which the damaged layer has been removed; a step of flattening the surface of the deposited intervening layer; a step of bonding the piezoelectric material substrate to a support substrate having a lower thermal expansion coefficient than the piezoelectric material, with the deposited intervening layer in between; and a step of thinning the piezoelectric material substrate after bonding. Lithium tantalate (LT) or lithium niobate (LN) are suitable as the piezoelectric material.

The present invention provides a PZN-based large-size ternary high-performance single crystal, a growing method and a molten salt furnace. The PZN-based large-size ternary high-performance single crystal is represented by formula (1-x-y)Pb(B′.sub.1/2B″.sub.1/2)O.sub.3-yPb(Zn.sub.1/3Nb.sub.2/3)O.sub.3-xPbTiO.sub.3, wherein B′ is Mg, Fe, Sc, Ni, In, Yb, Lu and/or Ho, B″ is Nb, Ta and/or W, 0.4<x<0.6, 0.1<y<0.4, 0.1<1-x-y<0.4. The present invention adjusts the convective change of the melt through the rotation of the top seed and the bottom crucible, overcoming the problems of serious crystal inclusions and poor crystal quality during the growth process, and can adapt the change of the crystal diameter to the thermal inertia of the heat preservation system, thus effectively reducing crystal inclusions and improving the yield of the crystal.

A laminated structure includes a crystalline substrate and a crystalline oxide film containing gallium as a main component and having a β-gallia structure, wherein the crystalline substrate is a crystalline substrate containing lithium tantalate as a main component. This provides an inexpensive laminated structure having a thermally stable crystalline oxide film.

A laminated structure includes a crystalline substrate and a crystalline oxide film containing gallium as a main component and having a β-gallia structure, wherein the crystalline substrate is a crystalline substrate containing lithium tantalate as a main component. This provides an inexpensive laminated structure having a thermally stable crystalline oxide film.

[Object]

An object of the present invention is to provide a method for manufacturing an oxide single crystal substrate having less dispersion in characteristics within the substrate surface.

[Means to solve the Problems]

In the manufacture method of the present invention, a powder containing a Li compound is dispersed in a medium to form a slurry, and heat is applied while the slurry is in contact with the surface of the oxide single crystal substrate, so as to diffuse Li into the substrate from the surface thereof to effect a modification of the substrate; or after the slurry is brought into contact with the surface of the oxide single crystal substrate, the oxide single crystal substrate is buried in a powder containing the Li compound, and heat is applied to effect the diffusion of Li in the substrate from the surface thereof whereby a modification of the substrate occurs.

[Object]

An object of the present invention is to provide a method for manufacturing an oxide single crystal substrate having less dispersion in characteristics within the substrate surface.

[Means to solve the Problems]

In the manufacture method of the present invention, a powder containing a Li compound is dispersed in a medium to form a slurry, and heat is applied while the slurry is in contact with the surface of the oxide single crystal substrate, so as to diffuse Li into the substrate from the surface thereof to effect a modification of the substrate; or after the slurry is brought into contact with the surface of the oxide single crystal substrate, the oxide single crystal substrate is buried in a powder containing the Li compound, and heat is applied to effect the diffusion of Li in the substrate from the surface thereof whereby a modification of the substrate occurs.

Provided are a composite substrate in which a wafer to be bonded has a sufficiently small surface roughness and which can be prevented from causing film peeling, and a method for producing the composite substrate. The composite substrate 40 of the present invention has a silicon wafer 10, an interlayer 11, and a single-crystal silicon thin film or oxide single-crystal thin film 20a stacked in the order listed and has a damaged layer 12a in a portion of the silicon wafer 10 on the side of the interlayer 11.

A layered solid element includes a ferroelectric layer of a crystalline material Li.sub.1−x(Nb.sub.1−yTa.sub.y).sub.1+xO.sub.3+2x−z which has X- or 33° Y-orientation with respect to a substrate of the layered solid element. The ferroelectric layer is grown epitaxially from a buffer layer having of one of the chemical formulae L.sub.kNi.sub.rO.sub.1.5.Math.(k+r)+w or L.sub.n+1Ni.sub.nO.sub.3n+1+δ, where L is a lanthanide element. Such layered solid element may form a thin-film bulk acoustic resonator and be useful for integrated electronic circuits such as RF-filters, or guided optical devices such as integrated optical modulators.