A method of fabricating a semiconductor structure is provided. The method includes evaporating at least one precursor and depositing an epitaxial film containing a halide perovskite derived from the at least one precursor on a single crystal substrate. Semiconductor structures made by the method are also provided.

An article includes a substrate that is substantially opaque to visible light and a coating disposed on the substrate. The coating includes a coating material having an inherent index of refraction, wherein the coating has an effective index of refraction that is less than the inherent index of refraction, and wherein the effective index of refraction is less than 1.8.

The invention relates to an evaporation cell (1) for vacuum evaporation chamber, the evaporation cell (1) comprising a crucible (5), the crucible (5) being adapted to receive a solid or liquid material to be sublimated or evaporated, heating means (3) to heat the material in the crucible, a nozzle (6) placed at an open end of the crucible (5), the nozzle (6) comprising a frustoconical portion (61) having an opening (60) adapted for the passage of a flow of evaporated or sublimated material towards the vacuum evaporation chamber, and a cover (7) placed on the nozzle (6), the cover (7) having an opening (70) arranged about the frustoconical portion (61) of the nozzle (6). According to the invention, the cover (7) has at least one frustoconical portion (71, 72, 73) arranged about the frustoconical portion (61) of the nozzle (6), the cover (7) forming a thermal barrier between the crucible (5) and the vacuum evaporation chamber.

Vapor phase transport systems and methods of depositing perovskite films are described. In an embodiment, a deposition method includes feeding a perovskite solution or constituent powder to a vaporizer, followed by vaporization and depositing the constituent vapor as a perovskite film. In an embodiment, a deposition system and method includes vaporizing different perovskite precursors in different vaporization zones at different temperatures, followed by mixing the vaporized precursors to form a constituent vapor, and depositing the constituent vapor as a perovskite film.

A method for preventing contamination of a substrate surface includes obtaining a substrate having a surface to be protected from contamination and depositing a removable protective salt coating on the substrate surface. A disclosed method also includes storing the substrate surface having the removable protective salt coating for a time period and then removing the protective salt coating. A method for selectively preventing atomic layer deposition (ALD) on a substrate surface exposed to an ALD process includes depositing a removable protective salt coating on the substrate surface, exposing the surface to an ALD process, and removing the protective salt coating. Some disclosed substrate surfaces include a thiol-on-gold monolayer, a silicon wafer, glass, a silanized surface, and a dental implant. The protective salt coating may have a thickness in the range of 50 nm to 1 μm. The protective salt coating may be deposited by thermal evaporation or similar process.

Deposition processes are disclosed herein for depositing thin films comprising a dielectric transition metal compound phase and a conductive or semiconducting transition metal compound phase on a substrate in a reaction space. Deposition processes can include a plurality of super-cycles. Each super-cycle may include a dielectric transition metal compound sub-cycle and a reducing sub-cycle. The dielectric transition metal compound sub-cycle may include contacting the substrate with a dielectric transition metal compound. The reducing sub-cycle may include alternately and sequentially contacting the substrate with a reducing agent and a nitrogen reactant. The thin film may comprise a dielectric transition metal compound phase embedded in a conductive or semiconducting transition metal compound phase.

Vapor phase transport systems and methods of depositing perovskite films are described. In an embodiment, a deposition method includes feeding a perovskite solution or constituent powder to a vaporizer, followed by vaporization and depositing the constituent vapor as a perovskite film. In an embodiment, a deposition system and method includes vaporizing different perovskite precursors in different vaporization zones at different temperatures, followed by mixing the vaporized precursors to form a constituent vapor, and depositing the constituent vapor as a perovskite film.

The present application provides a method for preparing a perovskite film, and a related perovskite film, solar cell and solar cell device thereof. The preparation method may include the steps of (1) providing a target material comprising the following elements: lead, a halogen, and one or more alkali metals; (2) sputtering using the target material in step (1), where a process gas is a noble gas, optionally, argon, so as to obtain a film; (3) subjecting the film obtained in step (2) to a chemical bath treatment, wherein the chemical bath is a solution of AX, A is selected from one or more of formamidine or methylamine, and X is a halogen; and (4) sputtering on the film obtained in step (3) using a tin metal, where a process gas comprises a noble gas, optionally, a mixture of argon and a halogen gas, so as to obtain the perovskite film.

The invention relates to a method for synthesis of films made of light-absorbing material with perovskite-like structure which can be used for fabrication of perovskite solar cells. The method for synthesis of films made of light-absorbing material with perovskite-like structure with a structural formula ACB.sub.3 is characterized by sequential deposition of a layer of a reagent C onto a layer of a reagent AB with a thickness determined by stoichiometry of the reaction followed by the immersion of the layers in a liquid or gaseous medium containing reagent B.sub.2 where component A states for CH.sub.3NH.sub.3.sup.+, (NH.sub.2).sub.2CH.sup.+, C(NH.sub.2).sub.3.sup.+, Cs.sup.+ or a mixture thereof, component B states for Cl.sup., Br.sup., I.sup. or a mixture thereof, component C states for metals Sn, Pb, Bi, or their melts, oxides, salts. The technical result achieved using the claimed invention is a simple and fast method for fabrication of a layer of light-absorbing organic-inorganic material with a perovskite-like structure which is homogeneous due to the formation of a film of the intermediate phase AB-B.sub.2 with improved morphology on the surfaces of a large area due to rapid crystallization, which allows the obtained material to be used in solar cells of large area.

A method for preparing an ultrathin two-dimensional (2D) monocrystalline nanosheet, the method including: 1) placing BiX.sub.3 powder where X=I, Br, or Cl in a crucible, and putting the crucible on a first heating zone of a furnace disposed at a gas inlet of a quartz tube; placing substrates covered with metal sheets on a second heating zone of the furnace disposed at a gas outlet of the quartz tube; 2) vacuumizing the quartz tube; pumping Ar gas into the quartz tube until the air pressure is 101.325 kPa; pumping a carrier gas into the quartz tube; and 3) heating and maintaining the second heating zone; heating the first heating zone for BiX.sub.3 evaporation until producing chemical reaction between BiX.sub.3 and the metal sheets, and preparing ultrathin 2D nanosheets on the substrates simultaneously; and cooling the substrate naturally to 15-30 C.