The invention relates to a method for growing a bulk single crystal, wherein the method comprises the steps of inserting a starting material into a crucible, melting the starting material in the crucible by heating the starting material, arranging a thermal insulation lid at a distance above a melt surface of said melt such that at least a central part of the melt surface is covered by the lid, and growing the bulk single crystal from the melt by controllably cooling the melt with the thermal insulation lid arranged above the melt surface.

Embodiments described herein relate generally to large scale synthesis of thinned graphite and in particular, few layers of graphene sheets and graphene-graphite composites. In some embodiments, a method for producing thinned crystalline graphite from precursor crystalline graphite using wet ball milling processes is disclosed herein. The method includes transferring crystalline graphite into a ball milling vessel that includes a grinding media. A first and a second solvent are transferred into the ball milling vessel and the ball milling vessel is rotated to cause the shearing of layers of the crystalline graphite to produce thinned crystalline graphite.

Embodiments described herein relate generally to large scale synthesis of thinned graphite and in particular, few layers of graphene sheets and graphene-graphite composites. In some embodiments, a method for producing thinned crystalline graphite from precursor crystalline graphite using wet ball milling processes is disclosed herein. The method includes transferring crystalline graphite into a ball milling vessel that includes a grinding media. A first and a second solvent are transferred into the ball milling vessel and the ball milling vessel is rotated to cause the shearing of layers of the crystalline graphite to produce thinned crystalline graphite.

An ingot includes a first surface, a second surface opposite to the first surface, and a third surface positioned along a first direction and connecting the first surface and the second surface. The ingot includes: a first pseudo single crystal region; an intermediate region containing one or more pseudo single crystal regions; and a second pseudo single crystal region. The first pseudo single crystal region, the intermediate region, and the second pseudo single crystal region are positioned adjacent sequentially in a second direction perpendicular to the first direction. In the second direction, a width of each of the first and second pseudo single crystal regions is larger than a width of the first intermediate region. Each of a boundary between the first pseudo single crystal region and the intermediate region and a boundary between the second pseudo single crystal region and the intermediate region includes a coincidence boundary.

An ingot includes a first surface, a second surface opposite to the first surface, and a third surface positioned along a first direction and connecting the first surface and the second surface. The ingot includes: a first pseudo single crystal region; an intermediate region containing one or more pseudo single crystal regions; and a second pseudo single crystal region. The first pseudo single crystal region, the intermediate region, and the second pseudo single crystal region are positioned adjacent sequentially in a second direction perpendicular to the first direction. In the second direction, a width of each of the first and second pseudo single crystal regions is larger than a width of the first intermediate region. Each of a boundary between the first pseudo single crystal region and the intermediate region and a boundary between the second pseudo single crystal region and the intermediate region includes a coincidence boundary.

A method for synthesizing an intergrown twin Ni.sub.2Mo.sub.6S.sub.6O.sub.2/MoS.sub.2 two-dimensional nanosheet with exposed (00L) crystal planes is disclosed. An Ni-Mo bonded precursor is formed by using an ion insertion method to restrict Ni ions to be located in a lattice matrix of a Mo-based compound; a dinuclear metal sulfide Ni.sub.2Mo.sub.6S.sub.6O.sub.2 is formed by precisely adjusting and controlling a concentration of a sulfur atmosphere and utilizing a reconstruction effect of Ni element in the lattice matrix of the Mo-based compound; and meanwhile, a growth direction of Ni.sub.2Mo.sub.6S.sub.6O.sub.2 is precisely adjusted and controlled by using a method for growing a single crystal in a limited area, so that Ni.sub.2Mo.sub.6S.sub.6O.sub.2 is grown, taking a single crystal MoS.sub.2 as a growth template, with the single crystal MoS.sub.2 alternately along a crystal plane (110) of the single crystal MoS.sub.2, so as to form a twin Ni.sub.2Mo.sub.6S.sub.6O.sub.2/MoS.sub.2 two-dimensional nanosheet in which Ni.sub.2Mo.sub.6S.sub.6O.sub.2and MoS.sub.2 are intergrown.

A method for synthesizing an intergrown twin Ni.sub.2Mo.sub.6S.sub.6O.sub.2/MoS.sub.2 two-dimensional nanosheet with exposed (00L) crystal planes is disclosed. An Ni-Mo bonded precursor is formed by using an ion insertion method to restrict Ni ions to be located in a lattice matrix of a Mo-based compound; a dinuclear metal sulfide Ni.sub.2Mo.sub.6S.sub.6O.sub.2 is formed by precisely adjusting and controlling a concentration of a sulfur atmosphere and utilizing a reconstruction effect of Ni element in the lattice matrix of the Mo-based compound; and meanwhile, a growth direction of Ni.sub.2Mo.sub.6S.sub.6O.sub.2 is precisely adjusted and controlled by using a method for growing a single crystal in a limited area, so that Ni.sub.2Mo.sub.6S.sub.6O.sub.2 is grown, taking a single crystal MoS.sub.2 as a growth template, with the single crystal MoS.sub.2 alternately along a crystal plane (110) of the single crystal MoS.sub.2, so as to form a twin Ni.sub.2Mo.sub.6S.sub.6O.sub.2/MoS.sub.2 two-dimensional nanosheet in which Ni.sub.2Mo.sub.6S.sub.6O.sub.2and MoS.sub.2 are intergrown.

A structure including a three-dimensionally stretchable single crystalline semiconductor membrane located on a substrate is provided. The structure is formed by providing a three-dimensional (3D) wavy silicon germanium alloy layer on a silicon handler substrate. A single crystalline semiconductor material membrane is then formed on a physically exposed surface of the 3D wavy silicon germanium alloy layer. A substrate is then formed on a physically exposed surface of the single crystalline semiconductor material membrane. The 3D wavy silicon germanium alloy layer and the silicon handler substrate are thereafter removed providing the structure.

A structure including a three-dimensionally stretchable single crystalline semiconductor membrane located on a substrate is provided. The structure is formed by providing a three-dimensional (3D) wavy silicon germanium alloy layer on a silicon handler substrate. A single crystalline semiconductor material membrane is then formed on a physically exposed surface of the 3D wavy silicon germanium alloy layer. A substrate is then formed on a physically exposed surface of the single crystalline semiconductor material membrane. The 3D wavy silicon germanium alloy layer and the silicon handler substrate are thereafter removed providing the structure.

Methods and wafers for low etch pit density, low slip line density, and low strain indium phosphide are disclosed and may include an indium phosphide single crystal wafer having a diameter of 4 inches or greater, having a measured etch pit density of less than 500 cm.sup.−2, and having fewer than 5 dislocations or slip lines as measured by x-ray diffraction imaging. The wafer may have a measured etch pit density of 200 cm.sup.−2 or less, or 100 cm.sup.−2 or less, or 10 cm.sup.−2 or less. The wafer may have a diameter of 6 inches or greater. An area of the wafer with a measured etch pit density of zero may at least 80% of the total area of the surface. An area of the wafer with a measured etch pit density of zero may be at least 90% of the total area of the surface.