Abstract: A process and apparatus which form a solar cell absorber on a surface of a workpiece as the workpiece and a carrier are advanced through a rapid thermal processing (RTP) chamber. In one embodiment, the surface of the workpiece includes a precursor layer and an absorber constituent is disposed on the carrier. Initially an absorber constituent vapor can be formed in the RTP chamber by advancing the carrier into the RTP chamber to vaporize the absorber constituent from the carrier. The workpiece with the precursor layer is then moved into the RTP chamber to react the absorber constituent vapor and the precursor layer to form an absorber layer on the workpiece.

Abstract: A system is described to deposit a buffer layer onto exposed surfaces of two different solar cell absorber layers of two different flexible workpieces from a process solution including all chemical components of the buffer layer material. The buffer layer is deposited from the process or deposition solution while the flexible workpieces are simultaneously heated and processed within a chamber in a face to face manner as the process solution is flown through a process gap formed between the exposed surfaces of the two solar cell absorber layers.

Abstract: A photovoltaic module which has at least two solar cells, and a method and system to manufacture such photovoltaic modules. The solar cells are disposed on a surface of an insulating carrier film and an isolation structure is formed between the solar cells to electrically isolate them. A conductor structure such as conductive fingers and busbars is formed on the module. The fingers are formed substantially on the top transparent conductive layer of the cells and the busbar is formed substantially over the insulation structure. The busbar electrically connects the top transparent conductive layer of one of the cells to the conductive base of the other cell.

Abstract: The present invention provides a method to form Group IBIIIAVIA solar cell absorber layers on continuous flexible substrates. In a preferred aspect, the method forms a Group IBIIIAVIA absorber layer for manufacturing photovoltaic cells by providing a workpiece having a precursor layer formed over a substrate, the precursor layer including copper, indium, gallium and selenium; heating the precursor layer to a first temperature; reacting the precursor layer at the first temperature for a first predetermined time to transform the precursor layer to a partially formed absorber structure; cooling down the partially formed absorber structure to a second temperature, wherein both the first temperature and the second temperature are above 400° C.; and reacting the partially formed absorber structure at the second temperature for a second predetermined time, which is longer than the first predetermined time, to form a Group IBIIIAVIA absorber layer.

Abstract: The present invention provides for new ohmic contact materials and diffusion barriers for Group IBIIIAVIA based solar cell structures, which eliminate two way diffusion while preserving the efficient ohmic contacts between the substrate and the absorber layers.

Abstract: A flexible solar cell assembly having solar cells that are positioned within a sealed module chamber. A sealed wiring chamber is positioned on an end of the sealed module chamber and is interposed between the sealed module chamber and a junction box. Wiring interconnecting the junction box to the solar cells in the sealed module chamber is routed through the sealed wiring chamber to inhibit water entry into the sealed module chamber via the wiring.

Abstract: An electrochemical deposition method to form uniform and continuous Group IIIA material rich thin films with repeatability is provided. Such thin films are used in fabrication of semiconductor and electronic devices such as thin film solar cells. In one embodiment, the Group IIIA material rich thin film is deposited on an interlayer that includes 20-90 molar percent of at least one of In and Ga and at least 10 molar percent of an additive material including one of Cu, Se, Te, Ag and S. The thickness of the interlayer is adapted to be less than or equal to about 20% of the thickness of the Group IIIA material rich thin film.

Abstract: The present inventions provide method and apparatus that employ constituents vaporized from one or more constituent supply source or sources to form one or more films of a precursor layer formed on a surface of a continuous flexible workpiece. Of particular significance is the implementation of vapor deposition systems that operate upon a horizontally disposed portion of a continuous flexible workpiece and a vertically disposed portion of a continuous flexible workpiece, preferably in conjunction with a short free-span zone of the portion of a continuous flexible workpiece.

Abstract: An electrochemical co-deposition method and solution to plate uniform, defect free and smooth (In,Ga)—Se films with repeatability and controllable molar ratios of (In,Ga) to Se are provided. Such layers are used in fabrication of semiconductor and electronic devices such as thin film solar cells. In one embodiment, the present invention provides an alkaline electrodeposition solution that includes an In salt, a Se acid or oxide, a tartrate salt as complexing agent for the In species, and a solvent to electrodeposit an In—Se film possessing sub-micron thickness on a conductive surface.

Abstract: A method of forming metallic connector patterns for solar cells, whereby an embosser having raised features shaped in the form of a metallic connector pattern is used to attach a portion of a metallic foil to a transparent conductive layer formed on a top transparent surface of a solar cell structure. The raised surfaces of the embosser press the metallic foil portion against the transparent conductive layer. Heat and pressure directed to the metallic foil portion attach the metallic foil portion to the underlying transparent conductive layer, and then the rest of the metallic foil, which is not attached to the transparent conductive layer, is removed.

Abstract: A multi step process, which forms a Group VIA material layer, such as a selenium (Se) layer, having a thickness greater than 500 nanometers. The process includes electroplating a Se material layer, which has an amorphous micro-structure and which exhibits high electrical resistivity, on a workpiece and subsequently annealing the Se layer. Annealing process transforms the amorphous structure of the Se layer into a crystalline structure which is conductive. After the annealing, another Se layer can be electroplated onto the annealed Se layer. The electroplating and annealing steps can be repeated until the desired Se layer thickness is reached.

Abstract: The present inventions generally relate to thin film solar cell fabrication, and more particularly, to techniques for interconnecting solar cells based on Group IBIIIAVIA thin film semiconductors. In a particular embodiment, a system is described that positions solar cells and conductive leads with respect to each other so that application of a conductive adhesive and formation of an assembled solar cell string, followed by curing and cooling of the conductive adhesive, can occur in a repeatable manner.

Abstract: A thin film solar cell including a Group IBIIIAVIA absorber layer on a defect free base including a stainless steel substrate is provided. The stainless steel substrate of the base is surface treated to reduce the surface roughness such as protrusions that cause shunts. In one embodiment, the surface roughness is reduced by coating surface with a thin silicon dioxide which fills the cavities and recesses around the protrusions and thereby reducing the surface roughness. After the silicon dioxide film is formed, a contact layer is formed over the ruthenium layer and the exposed portions of the substrate to complete the base.

Abstract: The present invention advantageously provides for, in different embodiments, low-cost deposition techniques to form high-quality, dense, well-adhering Group IBIIIAVIA compound thin films with macro-scale as well as micro-scale compositional uniformities. It also provides methods to monolithically integrate solar cells made on such compound thin films to form modules. In one embodiment, there is provided a method of growing a Group IBIIIAVIA semiconductor layer on a base, and includes the steps of depositing on the base a nucleation and/or a seed layer and electroplating over the nucleation and/or the seed layer a precursor film comprising a Group IB material and at least one Group IIIA material, and reacting the electroplated precursor film with a Group VIA material. Other embodiments are also described.

Abstract: The present inventions provide method and apparatus that employ constituents vaporized from one or more constituent supply source or sources to form one or more films of a precursor layer formed on a surface of a continuous flexible workpiece. Of particular significance is the implementation of vapor deposition systems that operate upon a horizontally disposed portion of a continuous flexible workpiece and a vertically disposed portion of a continuous flexible workpiece, preferably in conjunction with a short free-span zone of the portion of a continuous flexible workpiece.

Abstract: The present invention provides methods of manufacturing a high efficiency solar cell. In one embodiment, in a solar cell having a grid pattern that channels current, a defect causes an undesired current flow is removed by mechanically removing a portion of the grid pattern, thereby passivating the defect by removing a segment of the solar cell adjacent the defect. The segment also includes the front and back portions of the solar cell at the location of the defect without including the defect.

Abstract: A flexible solar cell assembly having solar cells that are positioned within a sealed module chamber. A sealed wiring chamber is positioned on an end of the sealed module chamber and is interposed between the sealed module chamber and a junction box. Wiring interconnecting the junction box to the solar cells in the sealed module chamber are routed through the sealed wiring chamber to inhibit water entry into the sealed module chamber via the wiring.

Abstract: The present invention provides a method to form Group IBIIIAVIA solar cell absorber layers on continuous flexible substrates. In a preferred aspect, the method forms a Group IBIIIAVIA absorber layer for manufacturing photovoltaic cells by providing a workpiece having a precursor layer formed over a substrate, the precursor layer including copper, indium, gallium and selenium; heating the precursor layer to a first temperature; reacting the precursor layer at the first temperature for a first predetermined time to transform the precursor layer to a partially formed absorber structure; cooling down the partially formed absorber structure to a second temperature, wherein both the first temperature and the second temperature are above 400° C.; and reacting the partially formed absorber structure at the second temperature for a second predetermined time, which is longer than the first predetermined time, to form a Group IBIIIAVIA absorber layer.

Abstract: An electrochemical deposition method and electrolyte to plate uniform, defect free and smooth gallium films are provided. In a preferred embodiment, the electrolyte may include a solvent that comprises water and at least one monohydroxyl alcohol, a gallium salt, and an acid to control the solution pH and conductivity. The method electrodeposits a gallium film possessing sub-micron thickness on a conductive surface. Such gallium layers are used in fabrication of semiconductor and electronic devices such as thin film solar cells.

Abstract: A solar cell including a high electrical resistivity transparent layer formed on a CdS buffer layer is provided. The high electrical resistivity transparent layer includes an intrinsic oxide film formed on the buffer layer and an intermediate oxide film formed on the intrinsic oxide film. The intrinsic oxide film includes undoped zinc oxide and has a thickness range of 10 to 40 nm. The intermediate oxide film includes semi-intrinsic zinc oxide doped with aluminum and has a thickness range of 50-150 nm. The intermediate oxide film has an aluminum concentration of less than 1000 ppm.