An article comprises a first portion comprising a first alloy and a second portion comprising a second alloy that is metallurgically bonded to the first portion to form a monolithic article. The metallurgical bonding involves the application of an electrical current across the bond line and results in a retention of a metallurgical structure of the first portion and of a metallurgical structure of the second portion immediately adjacent to a bond line. The first portion has a first dominant property and the second portion has a second dominant property. The first dominant property is different from the second dominant property. The first dominant property is selected to handle operating conditions at a first position of the article where the first portion is located and the second dominant property is selected to handle operating conditions at a second position of the article where the second portion is located.

Nanostructures including a first semiconductor nanocrystal including zinc and selenium, and a second semiconductor nanocrystal including a zinc chalcogenide, wherein a composition of the second semiconductor nanocrystal is different from a composition of the first semiconductor nanocrystal, wherein the nanostructures further include tellurium, wherein in the nanostructures, a mole ratio of selenium to tellurium is greater than or equal to about 0.83:1 and less than or equal to about 10:1, wherein a derivative thermogravimetry curve of the nanostructures has an extreme value in a temperature range of greater than or equal to about 250° C. and less than or equal to about 420° C.

Nanostructures including a first semiconductor nanocrystal including zinc and selenium, and a second semiconductor nanocrystal including a zinc chalcogenide, wherein a composition of the second semiconductor nanocrystal is different from a composition of the first semiconductor nanocrystal, wherein the nanostructures further include tellurium, wherein in the nanostructures, a mole ratio of selenium to tellurium is greater than or equal to about 0.83:1 and less than or equal to about 10:1, wherein a derivative thermogravimetry curve of the nanostructures has an extreme value in a temperature range of greater than or equal to about 250° C. and less than or equal to about 420° C.

A composite substrate according to includes: a support substrate; and a piezoelectric layer arranged on one side of the support substrate, wherein an amplitude of a waviness having a spatial frequency of more than 0.045 cyc/mm according to a shape of the support substrate is 10 nm or less.

The present invention provides a silicon carbide composite wafer and a manufacturing method thereof. The silicon carbide composite wafer includes (a) a silicon carbide material and (b) a wafer substrate, and the upper surface of the wafer substrate is bonded to the lower surface of the silicon carbide material, wherein the lower surface of the silicon carbide material and/or the upper surface of the wafer substrate undergo a surface modification, thereby allowing the silicon carbide material to be bonded to the wafer substrate directly and firmly. The technical effects of the present invention include achieving strong bonding between the wafer and the substrate, reducing manufacturing process, increasing yield rate, and achieving high industrial applicability.

A silicon wafer forming method includes: a block ingot forming step of cutting a silicon ingot to form block ingots; a planarizing step of grinding an end face of the block ingot to planarize the end face; a separation layer forming step of applying a laser beam of such a wavelength as to be transmitted through silicon to the block ingot, with a focal point of the laser beam positioned in the inside of the block ingot at a depth from the end face of the block ingot corresponding to the thickness of the wafer to be formed, to form a separation layer; and a wafer forming step of separating the silicon wafer to be formed from the separation layer.

Proposed are a layered compound having indium and phosphide, a nanosheet that may be prepared using the same, and an electrical device including the materials. Proposed is a layered compound represented by K.sub.1-xIn.sub.yP.sub.z (0≤x≤1.0, 0.75≤y≤1.25, 1.25≤z≤1.75).

A method for forming a diamond product. Diamond material is provided and a damage layer comprising sp.sup.2 bonded carbon is formed in the material. The presence of the damage layer defines a first diamond layer above and in contact with the damage layer and a second diamond layer below and in contact with the damage layer. The damage layer is electrochemically etched to separate it from the first layer, wherein the electrochemical etching is performed in a solution containing ions, the solution having an electrical conductivity of at least 500 μS cm.sup.−1, and wherein the ions are capable of forming radicals during electrolysis. The diamond product is also described.

The present invention relates to a method of bonding silicon parts using silicon powder and high-frequency heating device, the method comprising the steps of forming concave and convex coupling surfaces on the bonding surfaces of a lower ring and an upper ring; mounting the lower ring and the upper ring on a silicon part fusion bonding apparatus; injecting single crystal silicon powder into the concave and convex coupling surfaces on the bonding surfaces of the lower ring and the upper ring; and heating and fusing the bonding surfaces of the lower ring and the upper ring.

After separation layers are formed inside a single-crystal silicon ingot, a single-crystal silicon substrate is split off from the single-crystal silicon ingot with use of these separation layers as the point of origin. This can improve the productivity of the single-crystal silicon substrate compared with the case of manufacturing the single-crystal silicon substrate from the single-crystal silicon ingot by a wire saw.