The present disclosure generally relates to methods of preparing spherical salt particles for industrial, medical, and other uses. The methods can include combining the angular salt particles with a quantity of finishing media, for example, into a receptacle. Thereafter, the angular salt particles and the finishing media can be moved or agitated until the angular salt particles have a desired sphericity.

The present disclosure generally relates to methods of preparing spherical salt particles for industrial, medical, and other uses. The methods can include combining the angular salt particles with a quantity of finishing media, for example, into a receptacle. Thereafter, the angular salt particles and the finishing media can be moved or agitated until the angular salt particles have a desired sphericity.

[Object] It is an object of the present invention to provide a lithium tantalate single crystal substrate which undergoes only small warpage, is free from cracks and scratches, has better temperature non-dependence characteristics and a larger electromechanical coupling coefficient than a conventional Y-cut LiTaO.sub.3 substrate. [Means to solve the Problems] The lithium tantalate single crystal substrate of the present invention is a rotated Y-cut LiTaO.sub.3 single crystal substrate having a crystal orientation of 36° Y-49° Y cut characterized in that: the substrate is diffused with Li from its surface into its depth such that it has a Li concentration profile showing a difference in the Li concentration between the substrate surface and the depth of the substrate; and the substrate is treated with single polarization treatment so that the Li concentration is substantially uniform from the substrate surface to a depth which is equivalent to 5-15 times the wavelength of either a surface acoustic wave or a leaky surface acoustic wave propagating in the LiTaO.sub.3 substrate surface.

[Object] It is an object of the present invention to provide a lithium tantalate single crystal substrate which undergoes only small warpage, is free from cracks and scratches, has better temperature non-dependence characteristics and a larger electromechanical coupling coefficient than a conventional Y-cut LiTaO.sub.3 substrate. [Means to solve the Problems] The lithium tantalate single crystal substrate of the present invention is a rotated Y-cut LiTaO.sub.3 single crystal substrate having a crystal orientation of 36° Y-49° Y cut characterized in that: the substrate is diffused with Li from its surface into its depth such that it has a Li concentration profile showing a difference in the Li concentration between the substrate surface and the depth of the substrate; and the substrate is treated with single polarization treatment so that the Li concentration is substantially uniform from the substrate surface to a depth which is equivalent to 5-15 times the wavelength of either a surface acoustic wave or a leaky surface acoustic wave propagating in the LiTaO.sub.3 substrate surface.

A method of treating a substrate comprises applying an electric field to a substrate comprising a layer of a dopant on at least one surface; applying a predetermined temperature to the substrate in the electric field; applying the electric field and the predetermined temperature for a time sufficient to induce migration of the dopant into the substrate to provide a doped substrate; and removing the electric field and returning the doped substrate to about room temperature, wherein the doped substrate is characterized in that a spectral laser output of the doped substrate exhibits a nominally single frequency having a linewidth less than about 5 nm. The substrate may be a glass material, a single crystal material, a poly-crystalline material, a ceramic material, or a semiconductor material, which may be optically transparent. Before treatment, the substrate may be an undoped substrate or a doped substrate.

The present invention belongs to the field of semiconductor materials preparation technology, and relates to a preparation method of gallium oxide/copper gallium oxide heterojunction. In this method, the gallium oxide is pre-treated before the copper source is deposited on the pre-treated gallium oxide, or directly cover the copper source layer on the pretreated gallium oxide. Then, the gallium oxide with copper source is placed in a high temperature furnace in proper form and then heat treated for a certain time under certain conditions, so that the copper atomics can be controlled to diffuse into gallium oxide to form corresponding copper-gallium-oxygen alloys. Further the copper-gallium-oxygen alloys forms gallium oxide/copper gallium oxide heterojunction having good interfacial properties with gallium oxide which does not undergo copper diffusion. The advantage is that the high quality copper gallium oxide material can be prepared. The required equipment and process are simple and controllable.

A semiconductor wafer forms on a mold containing a dopant. The dopant dopes a melt region adjacent the mold. There, dopant concentration is higher than in the melt bulk. A wafer starts solidifying. Dopant diffuses poorly in solid semiconductor. After a wafer starts solidifying, dopant can not enter the melt. Afterwards, the concentration of dopant in the melt adjacent the wafer surface is less than what was present where the wafer began to form. New wafer regions grow from a melt region whose dopant concentration lessens over time. This establishes a dopant gradient in the wafer, with higher concentration adjacent the mold. The gradient can be tailored. A gradient gives rise to a field that can function as a drift or back surface field. Solar collectors can have open grid conductors and better optical reflectors on the back surface, made possible by the intrinsic back surface field.

A semiconductor wafer forms on a mold containing a dopant. The dopant dopes a melt region adjacent the mold. There, dopant concentration is higher than in the melt bulk. A wafer starts solidifying. Dopant diffuses poorly in solid semiconductor. After a wafer starts solidifying, dopant can not enter the melt. Afterwards, the concentration of dopant in the melt adjacent the wafer surface is less than what was present where the wafer began to form. New wafer regions grow from a melt region whose dopant concentration lessens over time. This establishes a dopant gradient in the wafer, with higher concentration adjacent the mold. The gradient can be tailored. A gradient gives rise to a field that can function as a drift or back surface field. Solar collectors can have open grid conductors and better optical reflectors on the back surface, made possible by the intrinsic back surface field.

A transparent timepiece component, in particular a watch glass, has a substantially planar or curved interior surface, and has mainly a transparent material colored by a zone of modified chemical composition within the component through an introduction of at least one coloring chemical element of the transparent material, this zone of modified chemical composition extending in one part only of the total thickness of the timepiece component.

A method for forming a power semiconductor device is provided. The method includes: providing a semiconductor wafer grown by a Czochralski process and having a first side; forming an n-type substrate doping layer in the semiconductor wafer at the first side, the substrate doping layer having a doping concentration of at least 10.sup.17/cm.sup.3; and forming an epitaxy layer on the first side of the semiconductor wafer after forming the n-type substrate doping layer.