Abstract: A photovoltaic cell for use in a single junction or multijunction photovoltaic device, which includes a p-type layer of a semiconductor compound including silicon, an i-type layer of an amorphous semiconductor compound including silicon, and an n-type layer of a semiconductor compound including silicon formed on the i-type layer. The i-type layer including an undoped first sublayer formed on the p-type layer, and a boron-doped second sublayer formed on the first sublayer.

Abstract: A multijunction photovoltaic device includes first and second amorphous silicon PIN photovoltaic cells in a stacked arrangement. An interface layer, composed of a doped silicon compound, is disposed between the two cells and has a lower bandgap than the respective n- and p-type adjacent layers of the first and second cells. The interface layer forms an ohmic contact with the one or the adjacent cell layers of the same conductivity type, and a tunnel junction with the other of the adjacent cell layers. The disclosed device is fabricated by a glow discharge process.

Abstract: A solar panel for use in a roof mounted array of solar panels, each panel having ridges protruding outwardly and adjacent to the side edges for receiving a standing seam cap between side-adjacent panels. Each solar panel is formed as an integral structure having a photovoltaic module an edge of which is sealed by a base substrate. The base substrate is configured to have lipped top and bottom edges which interlock to form a watertight seal between top-adjacent and bottom-adjacent solar panels. The solar panel array can be mounted on a roof, in place of shingles or the like, to provide environmental protection for the interior of a building.

Abstract: Photovoltaic apparatus includes a passivating oxide layer formed directly on the surface of a first conductivity type amorphous silicon material in a pattern corresponding substantially to a preselected metalized wide grid layer pattern. The patterned oxide layer is used as a mask to form a diffused layer of opposite conductivity type amorphous silicon material on those surface portions not covered by the oxide layer. The metalized grid layer is then formed on the oxide layer, covering the oxide layer, and overlapping the diffused opposite conductivity type layer at the edges to form continuous or intermittent ohmic contact areas with the diffused layer along the oxide layer-diffused layer boundaries.

Abstract: A textured layer of tin oxide on a vitreous substrate in which the thickness and degree of texture of the layer can be controlled independently of one another. The tin oxide fabricated by a process comprising steps of depositing a first film of tin oxide on the substrate by chemical vapor deposition from a first reactant mixture of tin chloride, water, and an alcohol and depositing a second film of tin oxide on the first tin oxide film by chemical vapor deposition from a second reactant mixture of tin chloride and water. Where the substrate is ordinary soda lime glass, it preferably is first coated with a film of silicon dioxide. The process permits deposition of substantially uniform layers of tin oxide in a continuous deposition process.

Abstract: An improved vertical junction solar cell wherein the vertical junctions are formed by a plurality of grooves etched in the silicon wafer of the solar cell. The grooves define a plurality of walls having a top surface and side surfaces and a plurality of groove bottoms therebetween. In order to increase radiation resistance in such vertical junction solar cells, a focusing coverslide is provided which retracts or reflects incident light onto only the top surfaces of the walls and away from the grooved bottoms. It has been discovered that the majority of the radiation degradation in vertical junction solar cells occurs as a result of incident light impinging on the grooved bottoms, which are less resistant to radiation than are the top walls. Thus, the present invention provides a vertical junction solar cell with greatly increased radiation resistivity.

Abstract: A photovoltaic cell that includes a transparent substrate, a front conductive layer formed on the substrate, a p-type layer formed on the front conductive layer, an i-layer of amorphous silicon formed on the p-layer, a wide bandgap n-type layer formed on the i-layer and a back contact layer formed on the n-type structure. The wide bandgap n-type layer may be an n-type sandwich structure which includes first, second, and third n-layers successively formed on one another. The first n-layer is formed on the i-layer, the second n-layer is formed on the first n-layer, and the n-layer is formed on the second n-layer. The second n-layer has an optical bandgap wider than the optical bandgap of the first and second n-type layers.

Abstract: A solar panel in which the bus-and-interconnect structures are visually masked, to improve not only aesthetics but also the operational characteristics of the panel. A transparent superstrate for the panel has on a surface juxtaposed to the radiation-receiving surfaces of the cells a pattern masking material just sufficient, with manufacturing tolerances, to mask the generally non-symmetrical interconnect structure in a substantially more uniform, symmetrical manner. The masking material may be matte-finish (paint) or highly reflective (a metallic deposit), and in either case may be applied by the same process (e.g., silk screen). The reflective mask structure inhibits heat build-up in the panel; and the matte-finish mask structure is generally unobtrusive and aesthetically pleasing, as required for example, in vehicular applications.

Abstract: An interconnect for electrically connecting adjacent solar cells disposed in a solar cell array is disclosed. The interconnect is comprised of three parts: an elongated stress relief part disposed substantially parallel to adjacent side edges of the solar cells which are electrically connected by the interconnect; a first connecting part joined to a first end portion of the stress relief part and to the electrical contact of the first solar cell; and a second connecting part joined to the opposite end portion of the stress relief part and to the electrical contact of the adjacent solar cell. In this manner, stress induced in the interconnect as a result of thermal cycling of the solar cells electrically connected by the interconnect is significantly reduced as compared to prior art configurations to thereby increase the survivability and expected life of the interconnect. In addition, the removal and replacement of the connected solar cells is facilitated.

Abstract: A method for encapsulating a photovoltaic module and an encapsulated photovoltaic module. The photovoltaic module includes a superstrate and one or more photovoltaic cells disposed on the superstrate. A barrier coating is applied to the exposed side of the photovoltaic module. The barrier coating is a mixture of a two component fluorinated polyurethane with 3-glycidoxy propyltrimethoxy silane. The photovoltaic module may also include an isolation scribe located around the perimeter of the exposed surface of the module.

Abstract: Compounds having the formula (MX.sub.3).sub.n M'X.sub.4-n wherein M and M' are different Group 4A atoms, at least one of M and M' is silicon, X is hydrogen, halogen or mixtures thereof, and n is an integer between 1 and 4, inclusive, are useful as deposition feedstock materials in the formation of hydrogenated amorphous silicon alloys useful in the fabrication of photovoltaic and other electronically active devices.Dopants having the formula (SiX.sub.3).sub.m L X.sub.3-m wherein L is a Group 5A atom selected from the group of phosphorous, arsenic, antimony and bismuth, X is hydrogen, halogen or mixtures thereof and m is an integer between 1 and 3, inclusive, are useful in the fabrication of negatively-doped hydrogenated amorphous silicon alloys useful in the fabrication of photovoltaic and other electronically active devices.Dopants having the formula YJX.sub.

Abstract: A method of forming laser-patterned conductive elements on a thin film of semiconductor material in a semiconductor device by fabricating a thin film of metal on the semiconductor material and scribing the semiconductor film along a desired pattern with a laser operated at a power density sufficient to ablate the semiconductor material along the desired pattern. The ablation of the semiconductor material produces gases that structurally weaken and burst through the metal film along the desired pattern to form gaps separating the metal film into a plurality of conductive elements, for example, back electrodes on a thin-film photovoltaic module.

Abstract: A method of forming a textured layer of tin oxide on a vitreous substrate in which the thickness and degree of texture of the layer can be controlled independently of one another. The method comprises the steps of depositing a first film of tin oxide on the substrate by chemical vapor deposition from a first reactant mixture of tin chloride, water, and an alcohol and depositing a second film of tin oxide on the first tin oxide film by chemical vapor deposition from a second reactant mixture of tin chloride and water. Where the substrate is ordinary soda lime glass, it preferably is first coated with a film of silicon dioxide. The method permits deposition of substantially uniform layers of tin oxide in a continuous deposition process.

Abstract: A method of fabricating spaced-apart back contacts on a thin film of semiconductor material by forming strips of buffer material on top of the semiconductor material in locations corresponding to the desired dividing lines between back contacts, forming a film of metal substantially covering the semiconductor material and buffer strips, and scribing portions of the metal film overlying the buffer strips with a laser without contacting the underlying semiconductor material to separate the metal layer into a plurality of back contacts. The buffer material serves to protect the underlying semiconductor material from being damaged during the laser scribing. Back contacts and multi-cell photovoltaic modules incorporating such back contacts also are disclosed.

Abstract: A portable photovoltaic battery recharger for simultaneously recharging a plurality of rechargeable batteries having different sizes and respective optimum charging current levels. The battery recharger includes a plurality of photovoltaic solar cells having a plurality of different selectively chosen surface areas for generating the respective optimum charging current levels when insolated, and battery receptacles for holding the plurality of rechargeable batteries in a recharging position. The plurality of solar cells are connected to the battery recepatcles to transmit the charging current generated by each photovoltaic cell to respective ones of the plurality of battery receptacles such that batteries held in the battery receptacles are charged at respective optimum charging current levels.

Abstract: A method of fabricating spaced-apart back contacts on a thin film of semiconductor material by forming strips of buffer material on top of the semiconductor material in locations corresponding to the desired dividing lines between back contacts, forming a film of metal substantially covering the semiconductor material and buffer strips, and scribing portions of the metal film overlying the buffer strips with a laser without contacting the underlying semiconductor material to separate the metal layer into a plurality of back contacts. The buffer material serves to protect the underlying semiconductor material from being damaged during the laser scribing. Back contacts and multi-cell photovoltaic modules incorporating such back contacts also are disclosed.

Abstract: A method for preparing a hydride containing at least two different Group 4A atoms wherein at least one of the Group 4A atoms is silicon or germanium. The method includes the steps of reacting an alkali metal and a macrocyclic compound with a silicon or germanium hydride to form a salt. The salt is then reacted with a Group 4A halide. The resulting hydrides are useful as deposition feedstock material for use in the formation of hydrogenated amorphous silicon alloy in the fabrication of photovoltaic devices and other semiconductor devices.

Abstract: A method of removing electrical shorts and shunts from a thin-film semiconductor device having pairs of electrodes with exposed contact surfaces wherein each pair of electrodes is separated by a semiconductor film. The disclosed method comprises the steps of coating the exposed contact surfaces with an ionic solution and successively applying a reverse-bias voltage between the exposed contact surfaces of each pair of electrodes. The ionic solution has an etching rate that increases with increased temperature so that the leakage current flowing through shorts and shunts located between each respective pair of electrodes in response to the reverse-bias voltage will create a local temperature increase at the shorts and shunts and selectively etch or oxidize the shorts and shunts, rendering them substantially nonconductive. The exposed contact surfaces can be coated using a sponge applicator or spray apparatus.

Abstract: Superlattice doped layers for amorphous silicon photovoltaic cells comprise a plurality of first and second lattices of amorphous silicon alternatingly formed on one another. Each of the first lattices has a first optical bandgap and each of the second lattices has a second optical bandgap different from the first optical bandgap. A method of fabricating the superlattice doped layers also is disclosed.

Abstract: Compounds having the formula (MX.sub.3).sub.n M'X.sub.4-n wherein M and M' are different Group 4A atoms, at least one of M and M' is silicon, X is hydrogen, halogen or mixtures thereof, and n is an integer between 1 and 4, inclusive, can be activated by dehydrogenation or dehalogenation. These compounds are useful as deposition feedstock materials in the formation of hydrogenated amorphous silicon alloys useful in the fabrication of photovoltaic and other electronically active devices.Dopants having the formula (SiX.sub.3).sub.m L X.sub.3-m wherein L is a Group 5A atom selected from the group of phosphorus, arsenic, antimony and bismuth, X is hydrogen, halogen or mixtures thereof and m is an integer between 1 and 3, inclusive, can be activated by dehydrogenation or dehalogenation. These compounds are useful in the fabrication of negatively-doped hydrogenated amorphous silicon alloys useful in the fabrication of photovoltaic and other electronically active devices.Dopants having the formula YJX.sub.