A method for post-treating an absorber layer for photoelectric conversion of incident light into electric current. The method includes providing a chalcogen-containing absorber layer on a carrier, applying a post-treatment layer on a surface of the absorber layer, wherein the post-treatment material is not a buffer or component of a buffer, and thermally diffusing the post-treatment material into the absorber layer. A method for producing a layer system for the production of thin-film solar cells is also described.

A system for manufacture of I-III-VI-absorber photovoltaic cells involves sequential deposition of films comprising one or more of silver and copper, with one or more of aluminum indium and gallium, and one or more of sulfur, selenium, and tellurium, as compounds in multiple thin sublayers to form a composite absorber layer. In an embodiment, the method is adapted to roll-to-roll processing of photovoltaic cells. In an embodiment, the method is adapted to preparation of a CIGS absorber layer having graded composition through the layer of substitutions such as tellurium near the base contact and silver near the heterojunction partner layer, or through gradations in indium and gallium content. In a particular embodiment, the graded composition is enriched in gallium at a base of the layer, and silver at the top of the layer. In an embodiment, each sublayer is deposited by co-evaporation of copper, indium, gallium, and selenium, which react in-situ to form CIGS. In a particular embodiment, a special selenium or tellurium source, valve and delivery subsystem is made of quartz, graphite, coated graphite, or molybdenum. In a particular embodiment, an ion-beam source module configured for surface smoothing the solar absorber sublayer surface before passing through the final deposition zone.

A preparation method of the light absorption layer of a copper-indium-gallium-sulfur-selenium film solar cell is provided. The method employs a non-vacuum liquid-phase chemical technique, which comprises following steps: forming source solution containing copper, indium, gallium, sulfur and selenium; using the solution to form a precursor film on a substrate by a non-vacuum liquid-phase process; drying and annealing the precursor film. Thus, a compound film of copper-indium-gallium-sulfur-selenium is gained.

A composite material is described. The composite material comprises semiconductor nanocrystals, and organic molecules that passivate the surfaces of the semiconductor nanocrystals. One or more properties of the organic molecules facilitate the transfer of charge between the semiconductor nanocrystals. A semiconductor material is described that comprises p-type semiconductor material including semiconductor nanocrystals. At least one property of the semiconductor material results in a mobility of electrons in the semiconductor material being greater than or equal to a mobility of holes. A semiconductor material is described that comprises n-type semiconductor material including semiconductor nanocrystals. At least one property of the semiconductor material results in a mobility of holes in the semiconductor material being greater than or equal to a mobility of electrons.

A layer of an n-type chalcogenide compositions provided on a substrate in the presence of an oxidizing gas in an amount sufficient to provide a resistivity to the layer that is less than the resistivity a layer deposited under identical conditions but in the substantial absence of oxygen.

Designs of extremely high efficiency solar cells are described. A novel alternating bias scheme enhances the photovoltaic power extraction capability above the cell band-gap by enabling the extraction of hot carriers. When applied in conventional solar cells, this alternating bias scheme has the potential of more than doubling their yielded net efficiency. When applied in conjunction with solar cells incorporating quantum wells (QWs) or quantum dots (QDs) based solar cells, the described alternating bias scheme has the potential of extending such solar cell power extraction coverage, possibly across the entire solar spectrum, thus enabling unprecedented solar power extraction efficiency. Within such cells, a novel alternating bias scheme extends the cell energy conversion capability above the cell material band-gap while the quantum confinement structures are used to extend the cell energy conversion capability below the cell band-gap. Light confinement cavities are incorporated into the cell structure in order to allow the absorption of the cell internal photo emission, thus further enhancing the cell efficiency.

Methods and semiconductor materials produced by such methods that are suitable for use in photovoltaic cells, solar cells fabricated with such methods, and solar panels composed thereof. Such methods include a wet-chemical synthesis method capable of producing a Group I-III-VI.sub.2 semiconductor material by forming a solution containing an organic solvent, at least one Group I precursor of at least one Group I element, and at least one Group III precursor of at least one Group III element. The Group I precursor is present in the solution in an amount of less than 120% of a stoichiometric ratio of the Group I element in the Group I-III-VI.sub.2 semiconductor material, and the Group III precursor is present in the solution in an amount of greater than 55% of a stoichiometric ratio of the Group III element in the Group I-III-VI.sub.2 semiconductor material.

A method of fabricating a color tunable thin film photovoltaic device includes depositing a layer of a semiconducting compound configured to exhibit a photovoltaic effect, and depositing a buffer layer over the layer of the semiconducting compound. Depositing transparent conducting oxides (TCO) over the buffer layer is followed by selecting two or more layers of optically transparent materials such that constructive interference among wavelengths reflected by the buffer layer, the TCO, and the two or more layers results in a desired exhibited color and depositing the two or more layers of the optically transparent materials above the TCO.

A method for producing an intermediate product for obtaining a photovoltaic module comprising a plurality of solar cells, said method comprising the following steps: (a) localized deposition on a substrate (4) of a layer of metal (8) so as to cover at least one portion (401) of the substrate, (b) deposition on this localized layer (8) of a layer (41) of conductive material, said layer coating the localized layer (8).

A semiconductor device including pixels arranged in a matrix of n rows and m columns, in which the pixels in the m-th column are shielded from light, is provided.