Provided are a complex of heterogeneous two-dimensional materials and a method of manufacturing the same. The complex of heterogeneous two-dimensional materials may include a substrate; a first two-dimensional material layer on the substrate and having a two-dimensional crystal structure; and a second two-dimensional material layer between the substrate and the first two-dimensional material layer. The second two-dimensional material layer have a two-dimensional crystal structure in which a plurality of phosphorus atoms are covalently bonded to each other.

The present disclosure provides a method of preparing a chalcogen containing solution that is hydrazine free and hydrazinium free, wherein the method comprises: providing a predetermined amount of elemental chalcogen; providing a predetermined amount of elemental sulfur; providing an amine solvent; and combining the predetermined amount of elemental chalcogen and the predetermined amount of elemental sulfur in the amine solvent, thereby dissolving the elemental chalcogen and the elemental sulfur in the amine solvent. The chalcogen containing solution can advantageously be used as a precursor for the formation of a chalcogen containing layer on a substrate.

Embodiments described herein include a method for forming a vertical hetero-stack and a device including a vertical hetero-stack. An example method is used to form a vertical hetero-stack of a first nanostructure and a second nanostructure arranged on an upper surface of the first nanostructure. The first nanostructure is formed by a first transition metal dichalcogenide, TMDC, material and the second nanostructure is formed by a second TMDC material. The example method includes providing the first nanostructure on a substrate. The method also includes forming a reactive layer of molecules on the first nanostructure along a periphery of the upper surface. The method further includes forming the second nanostructure by a vapor deposition process. The second TMDC material nucleates on the reactive layer of molecules along the periphery and grows laterally therefrom to form the second nanostructure on the upper surface.

Methods of producing a self-aligned structure comprising a metal chalcogenide are described. Some methods comprise forming a metal-containing film in a substrate feature and exposing the metal-containing film to a chalogen precursor to form a self-aligned structure comprising a metal chalcogenide. Some methods comprise forming a metal-containing film in a substrate feature, expanding the metal-containing film to form a pillar and exposing the pillar to a chalogen precursor to form a self-aligned structure comprising a metal chalcogenide. Some methods comprise directly forming a metal chalcogenide pillar in a substrate feature to form a self-aligned structure comprising a metal chalcogenide. Methods of forming self-aligned vias are also described.

A method (200) and deposition zone apparatus (300) for fabricating thin-film optoelectronic devices (100), the method comprising: providing a potassium-nondiffusing substrate (110), forming a back-contact layer (120); forming at least one absorber layer (130) made of an ABC chalcogenide material, adding at least two different alkali metals, and forming at least one front-contact layer (150) wherein one of said at least two different alkali metals is potassium and where, following forming said front-contact layer, in the interval of layers (470) from back-contact layer (120), exclusive, to front-contact layer (150), inclusive, the comprised amounts resulting from adding at least two different alkali metals are, for potassium, in the range of 500 to 10000 ppm and, for the other of said at least two different alkali metals, in the range of 5 to 2000 ppm and at most ½ and at least 1/2000 of the comprised amount of potassium. The method (200) and apparatus (300) are advantageous for more environmentally-friendly production of photovoltaic devices (100) on flexible substrates with high photovoltaic conversion efficiency and faster production rate.

A method is for depositing a thin tungsten and/or molybdenum sulfide film on a substrate chemically, under vacuum.

A method for producing a substantially planar surface for semiconductor processing to improve lithography, planarization, and other process steps that benefit from a flat substrate. The method includes depositing a first alloy to form a first layer on a substrate. The first layer has a center high deposition, meaning the height in the center of the substrate is higher than the height at the edges of the substrate. The method further includes depositing a second alloy on the first layer to form a second layer. The first alloy has a different composition than the second alloy. In such a method the net deposition is substantially planar reducing or eliminating deposition induced long-range distortions that might occur across a substrate.

A method for producing a layer system for thin-film solar cells is described, wherein a) an absorber layer is produced, and b) a buffer layer is produced on the absorber layer, wherein the buffer layer contains sodium indium sulfide according to the formula Na.sub.xIn.sub.y-x/3S with 0.063≦x≦0.625 and 0.681≦y≦1.50, and wherein the buffer layer is produced, without deposition of indium sulfide, based on at least one sodium thioindate compound.

The present disclosure provides a semiconductor device in accordance with some embodiments. The semiconductor device includes a first transition metal dichalcogenide film on a substrate; a second transition metal dichalcogenide film on the first transition metal dichalcogenide film; source and drain features formed over the second transition metal dichalcogenide film; and a first gate stack formed over the second transition metal dichalcogenide film and interposed between the source and drain feature.

Disclosed is a method of making a conductive material or active material that includes graphene or other 2-D materials. The method includes obtaining a layered stack. The layered stack including one or more conductive materials or 2-D materials separated by a metal layer, and one or more substrate materials. The stack can be subjected to a metal removal process to obtain two conductive or active materials. A first conductive or active material can include a first substrate layer attached to the first active layer. The second conductive or active material can include a second substrate layer attached to the second active layer. The first and second active layers can be conductive graphene layers.