Abstract: A method of fabricating a photovoltaic device includes a step of forming an absorber layer above a substrate, and a step of forming a surface layer on the absorber layer. The absorber layer includes an I-III-VI2 compound, which contains a Group I element, a Group III element and a Group VI element. The surface layer includes an I-III-VI2 compound, which contains a Group I element, a Group III element and a Group VI element, and has an atomic ratio of the Group I element to the Group III element in the range of from 0.1 to 0.9.

Abstract: Provided is a structure and method for forming CIS-based absorber layers for thin-film solar cells that include three-dimensional compositional profiles. The disclosure provides a patterned absorber layer with two or more different regions, each of the regions having a different concentration profile of one or more components. In some embodiments, the different regions have different respective GGI profiles. GGI represents an atomic ratio of Ga/(Ga+In) in CIS-based absorber materials and in some embodiments the two or more different regions have GGI gradients from top to bottom of the CIS-based absorber layer. The method includes using two evaporation sources in a co-evaporation system to produce the two or more different regions adjacent one another on a substrate.

Abstract: A solar cell has a back contact layer over a substrate. The substrate has a scribe line extending through it. An absorber layer is over the back contact layer. A front contact layer is over the absorber layer. The front contact layer has a first end and a second end opposite the first end. The scribe line is closer to the second end than to the first end. The front contact layer has a thickness above the first end that is greater than the thickness of the front contact layer at the scribe line.

Abstract: A method of fabricating a photovoltaic cell, and apparatus formed by the method, yields increased quantum efficiency. A back contact layer is formed above a substrate. An absorber layer is formed above the back contact layer. A buffer layer is formed above the absorber layer. A transparent conductive layer is formed above the buffer layer. A surface of the transparent conductive layer is treated with an acid to increase roughness of the surface.

Abstract: Provided are methods for forming antireflective layers on solar cells using wet chemical processes and solar cells with anti-reflective layers formed of ZnO based nanorods. Self-assembling ZnO nanorods are generated in the chemical solution without any catalysts. The nanorods are formed to different shapes such as hexagonal, cubic, and circular in cross-section. The refractive index of the ARC layer formed of the nanorods is modulated by controlling the diameter and length of the nanorods by controlling the Molarity of the solution used to form the nanorods. A correlation is established between the refractive index and solution Molarity and a solution is prepared with the desired Molarity. The nanorods are formed from HMT ([CH2]6NH4) and a dissociative Zn2+/OH? chemical such as Zn(NO3)2.

Abstract: An evaporation apparatus comprises a chamber configured to contain at least one dispensing nozzle and at least one substrate to be coated. The chamber has at least one adjustable shielding member defining an adjustable aperture. The member is positioned between the at least one dispensing nozzle and the at least one substrate. The aperture is adjustable in at least one of the group consisting of area and shape. The at least one adjustable shielding member has a heater.

Abstract: A solar cell device and a method of fabricating the same is described. The solar cell includes a back contact, an absorber over the back contact, and a front contact over the absorber. The back contact includes a back electrode layer and a graphene layer.

Abstract: An apparatus for forming a solar cell includes a housing defining a vacuum chamber, a rotatable substrate support, at least one inner heater and at least one outer heater. The substrate support is inside the vacuum chamber configured to hold a substrate. The at least one inner heater is between a center of the vacuum chamber and the substrate support, and is configured to heat a back surface of a substrate on the substrate support. The at least one outer heater is between an outer surface of the vacuum chamber and the substrate support, and is configured to heat a front surface of a substrate on the substrate support.

Abstract: A solar cell device and a method of fabricating the same are described. The method of fabricating a solar cell includes forming a photovoltaic substructure including a substrate, back contact, absorber and buffer, forming a transparent cover separate from the photovoltaic substructure including a transparent layer and a plasmonic nanostructured layer in contact with the transparent layer, and adhering the transparent cover on top of the photovoltaic substructure. The plasmonic nanostructured layer can include metal nanoparticles.

Abstract: A method includes depositing spacers at a plurality of locations directly on a back contact layer over a solar cell substrate. An absorber layer is formed over the back contact layer and the spacers. The absorber layer is partially in contact with the spacers and partially in direct contact with the back contact layer. The solar cell substrate is heated to form voids between the absorber layer and the back contact layer at the locations of the spacers.

Abstract: A method for manufacturing a CIGS thin film photovoltaic device includes forming a back contact layer on a substrate, forming an Se-rich layer on the back contact layer, forming a precursor layer on the Se-rich layer by depositing copper, gallium and indium resulting in a first interim structure, annealing or selenizing the first interim structure, thereby forming Cu/Se, Ga/Se or CIGS compounds along the interface between the back contact layer and the precursor layer and resulting in a second interim structure, and selenizing the second interim structure, thereby converting the precursor layer into a CIGS absorber layer on the back contact layer.

Abstract: A method of fabricating a photovoltaic device includes forming an absorber layer comprising an absorber material above a substrate, forming a buffer layer over the absorber layer, forming a front transparent layer over the buffer layer, and exposing the photovoltaic device to heat or radiation at a temperature from about 80° C. to about 500° C. for a period of time, subsequent to the step of forming a buffer layer over the absorber layer.

Abstract: A method for fabricating a solar cell generally comprises delivering a solar cell substructure to a chamber. Electromagnetic radiation is generated using a wave generating device that is coupled to the chamber such that the wave generating device is positioned proximate to the solar cell substructure. The electromagnetic radiation is applied onto at least a portion of the solar cell substructure to facilitate the diffusion of at least one metal element through at least a portion of the solar cell substructure such that a semiconductor interface is formed between at least two different types of semiconductor materials of the solar cell substructure.

Abstract: A device and method of improving efficiency of a thin film solar cell by providing a back reflector between a back electrode layer and an absorber layer. Back reflector reflects sunlight photons back into the absorber layer to generate additional electrical energy. The device is a photovoltaic device comprising a substrate, a back electrode layer, a back reflector, an absorber layer, a buffer layer, and a front contact layer. The back reflector is formed as a plurality of parallel lines.

Abstract: A solar string includes first and second solar modules coupled to first and second filters by an electric transmission line. The second solar module includes a solar panel including a plurality of photovoltaic cells configured to convert photon energy to electrical energy. A processor is coupled to the solar panel and is in communication with the first solar module. The processor is configured to monitor an output of the solar panel and to transmit a status signal including an environmental condition of the second solar module to the first solar module by way of the electric transmission line. The first and second filters are configured to pass electrical power to a central inverter of a solar array in which the solar string is disposed and to prevent the status signal transmitted from the second solar module to the first solar module from being transmitted to the central inverter.

Abstract: In a method of forming a CIGS film absorption layer, a first precursor is provided including a first substrate having a major process precursor film formed thereon, the major process precursor film containing two or more of Cu, In, Ga, and Se. A second precursor is provided including a second substrate having an element supplying precursor film formed thereon, the element supply precursor film containing two or more of Cu, In, Ga and Se. The precursors are oriented with the major process precursor film and element supplying precursor film facing one another so as to allow diffusion of elements between the films during annealing. The oriented films are annealed and then the precursors are separated, wherein the CIGS film is formed over the first substrate and either a CIGS film or a precursor film containing two or more of Cu, In, Ga, and Se remains over the second substrate.

Abstract: A method and system for forming chalcogenide semiconductor absorber materials with sodium impurities is provided. The system includes a sodium vaporizer in which a solid sodium source material is vaporized. The sodium vapor is added to reactant gases and/or annealing gases and directed to a furnace that includes a substrate with a metal precursor material. The precursor material reacts with reactant gases such as S-containing gases and Se-containing gases according to various process sequences. In one embodiment, a selenization operation is followed by an annealing operation and a sulfurization operation and the sodium vapor is caused to react with the metal precursor during at least one of the annealing and the sulfurization steps to produce a chalcogenide semiconductor absorber material that includes sodium dopant impurities.

Abstract: A photovoltaic device includes a substrate; a back contact layer disposed on the substrate; an absorber layer for photo absorption disposed above the back contact layer; a buffer layer disposed above the absorber layer; a front contact layer disposed above the buffer layer; and a plasmonic nanostructured layer having a plurality of nano-particles, wherein the plasmonic nanostructured layer is between a topmost back contact layer surface and the absorber layer.

Abstract: An apparatus includes a manifold coupled to a vapor source, the manifold having a plurality of nozzles, an inner cylinder, and an outer cylinder containing the inner cylinder with a space defined between the inner and outer cylinders. One of the inner cylinder or outer cylinder is rotatable with respect to the other of the inner cylinder or outer cylinder. The outer cylinder has an inlet coupled to the manifold to receive vapor from the nozzles. The outer cylinder has an outlet for dispensing the vapor.

Abstract: A photovoltaic system includes a photovoltaic module having an upper surface. A fluid deposition unit is positioned to deposit a layer of a fluid on the upper surface of the photovoltaic module. A fluid collection unit is positioned to collect fluid deposited on the upper surface of the photovoltaic module. A fluid reservoir is connected to receive fluid from the fluid collection unit. A pump is connected to supply fluid from the fluid reservoir to the fluid deposition unit.