Abstract: Thin film photovoltaic devices are provided that generally include a transparent conductive oxide layer on the glass, a multi-layer n-type stack on the transparent conductive oxide layer, and an absorber layer (e.g., a cadmium telluride layer) on the multi-layer n-type stack. The multi-layer n-type stack generally includes a first layer (e.g., a cadmium sulfide layer) and a second layer (e.g., a mixed phase layer). The multi-layer n-type stack can, in certain embodiments, include additional layers (e.g., a third layer, a fourth layer, etc.). Methods are also generally provided for manufacturing such thin film photovoltaic devices.

Abstract: Cadmium telluride based thin film photovoltaic devices are generally described. The device can include a transparent conductive oxide layer on a substrate. A plurality of metal gridlines can directly contact the transparent conductive oxide layer, and can be oriented in a first direction. A cadmium sulfide layer can be included on the transparent conductive oxide layer, and a cadmium telluride layer can be included on the cadmium sulfide layer. A plurality of scribe lines can be defined through the thickness of the cadmium sulfide layer and the cadmium telluride layer to define a plurality of photovoltaic cells such that the plurality of scribe lines are oriented in a second direction that intersects with the first direction.

Abstract: A cadmium telluride thin film photovoltaic device is provided having a thin film interlayer positioned between a cadmium sulfide layer and a cadmium telluride layer. The thin film interlayer can be an oxide thin film layer (e.g., an amorphous silica layer, a cadmium stannate layer, a zinc stannate layer, etc.) or a nitride film, and can act as a chemical barrier at the p-n junction to inhibit ion diffusion between the layers. The device can include a transparent conductive layer on a glass superstrate, a cadmium sulfide layer on the transparent conductive layer, a thin film interlayer on the cadmium sulfide layer, a cadmium telluride layer on the thin film interlayer, and a back contact on the cadmium telluride layer. Methods are also provided of manufacturing such devices.

Abstract: A system is provided for heating or cooling discrete, linearly conveyed substrates having a gap between a trailing edge of a first substrate and a leading edge of a following substrate in a conveyance direction. The system includes a chamber, and a conveyor operably configured within the chamber to move the substrates through at a conveyance rate. A plurality of individually controlled temperature control units, for example heating or cooling units, are disposed linearly within the chamber along the conveyance direction. A controller is in communication with the temperature control units and is configured to cycle output of the temperature control units from a steady-state temperature output as a function of the spatial position of the conveyed substrates within the chamber relative to the temperature control units so as to decrease temperature variances in the substrates caused by movement of the substrates through the chamber.

Abstract: Methods for forming a conductive oxide layer on a substrate are provided. The method can include sputtering a transparent conductive oxide layer (“TCO layer”) on a substrate from a target (e.g., including cadmium stannate) at a sputtering temperature of about 10° C. to about 100° C. The TCO layer can then be annealed in an anneal temperature comprising cadmium at an annealing temperature of about 500° C. to about 700° C. The method of forming the TCO layer can be used in a method for manufacturing a cadmium telluride based thin film photovoltaic device, further including forming a cadmium sulfide layer over the transparent conductive oxide layer and forming a cadmium telluride layer over the cadmium sulfide layer.

Abstract: Methods are generally provided for manufacturing such thin film photovoltaic devices via sputtering a mixed phase layer from a target (e.g., at least including CdSOx, where x is 3 or 4) on a transparent conductive oxide layer and depositing a cadmium telluride layer on the mixed layer. The transparent conductive oxide layer is on a glass substrate.

Abstract: Methods for forming a TCO layer on a substrate are generally provided and include sputtering a TCO layer on a substrate from a target including cadmium stannate. A cap material (e.g., including cadmium) is deposited onto an outer surface of an indirect anneal system, and the TCO layer can be annealed at an anneal temperature while in contact with or within about 10 cm of the cap material. An anneal oven is also generally provided and includes an indirect anneal system defining a deposition surface and an anneal surface such that a cap material deposited on the anneal surface of the indirect anneal system is positioned to be in contact with or within about 10 cm of a thin film on the substrate. A cap material source can be positioned to deposit the cap material onto the deposition surface such that the anneal surface comprises the cap material.

Abstract: An apparatus and associated method for vapor deposition of a sublimated source material as a thin film on a photovoltaic (PV) module substrate includes a deposition head wherein a source material is sublimated. A distribution manifold is provided with a plurality of passages defined therethrough for passage of the sublimated source material to the substrate. A shutter plate is disposed above the distribution manifold and includes a plurality of passages therethrough that align with the passages in the distribution manifold in a first position of the shutter plate. The shutter plate is movable to a second position wherein the shutter plate blocks the passages in the distribution manifold to flow of sublimated material therethrough. A lifting mechanism is configured between the shutter plate and the distribution manifold to lift and move the shutter plate between the first and second positions without sliding the shutter plate on the distribution manifold.

Abstract: Apparatus and processes for thin film deposition of semiconducting layers in the formation of cadmium telluride thin film photovoltaic device are provided. The apparatus includes a series of integrally connected chambers, such as a load vacuum chamber connected to a load vacuum pump; a sputtering deposition chamber; a vacuum buffer chamber; and, a vapor deposition chamber. A conveyor system is operably disposed within the apparatus and configured for transporting substrates in a serial arrangement into and through the load vacuum chamber, the sputtering deposition chamber, the vacuum buffer chamber, and the vapor deposition chamber at a controlled speed. The sputtering deposition chamber; the vacuum buffer chamber; and the vapor deposition chamber are integrally connected such that the substrates being transported through the apparatus are kept at a system pressure less than about 760 Torr.

Abstract: Methods for laser scribing a film stack including a plurality of thin film layers on a substrate are provided. A pulse of a laser beam is applied to the film stack, where the laser beam has a power that varies as a function of time during the pulse according to a predetermined power cycle. For example, the pulse can have a pulse lasting about 0.1 nanoseconds to about 500 nanoseconds. This pulse of the laser beam can be repeated across the film stack to form a scribe line through at least one of the thin film layers on the substrate. Such methods are particularly useful in laser scribing a cadmium telluride thin-film based photovoltaic device.

Abstract: An apparatus and related process are provided for vapor deposition of a sublimated source material as a thin film on a photovoltaic (PV) module substrate. A receptacle is disposed within a vacuum head chamber and is configured for receipt of a source material. A heated distribution manifold is disposed below the receptacle and includes a plurality of passages defined therethrough. The receptacle is indirectly heated by the distribution manifold to a degree sufficient to sublimate source material within the receptacle. A molybdenum distribution plate is disposed below the distribution manifold and at a defined distance above a horizontal plane of a substrate conveyed through the apparatus. The molybdenum distribution plate includes a pattern of holes therethrough that further distribute the sublimated source material passing through the distribution manifold onto the upper surface of the underlying substrate. The molybdenum distribution plate includes greater than about 75% by weight molybdenum.

Abstract: An active viewport assembly for use in detecting substrates conveyed through a vapor deposition system includes a casing configured for mounting to a wall of a vapor deposition module. The casing further includes an enclosed chamber, an exterior side port, and an interior side port. A lens assembly is disposed within the chamber and extends through the interior side port. A heater element is configured on the lens assembly within the chamber. One of an active transmitter or an active signal receiver is configured with the exterior side port external of the chamber and is axially aligned with and spaced from the lens assembly.

Abstract: Apparatus is generally provided for vapor deposition of a sublimated source material as a thin film on a photovoltaic module substrate. The apparatus includes a distribution plate disposed below the distribution manifold and at a defined distance above a horizontal conveyance plane of an upper surface of a substrate conveyed through the apparatus. The distribution plate defines a pattern of passages therethrough configured to provide greater resistance to the flow of sublimated source vapors at a first longitudinal end than a second longitudinal end. A process for vapor deposition of a sublimated source material to form thin film on a photovoltaic module substrate is also provided via distributing the sublimated source material onto an upper surface of the substrates through a distribution plate positioned between the upper surface of the substrate and the receptacle.

Abstract: Thin film photovoltaic devices are provided that generally include a transparent conductive oxide layer on the glass, a multi-layer n-type stack on the transparent conductive oxide layer, and a cadmium telluride layer on the multi-layer n-type stack. The multi-layer n-type stack generally includes a first layer and a second layer, where the first layer comprises cadmium and sulfur and the second layer comprises cadmium and oxygen. The multi-layer n-type stack can, in certain embodiments, include additional layers (e.g., a third layer, a fourth layer, etc.). Methods are also generally provided for manufacturing such thin film photovoltaic devices.

Abstract: Thin film photovoltaic devices are generally provided. The device can include a transparent conductive oxide layer on a glass substrate, an n-type thin film layer on the transparent conductive layer, and a p-type thin film layer on the n-type layer. The n-type thin film layer and the p-type thin film layer form a p-n junction. An anisotropic conductive layer is applied on the p-type thin film layer, and includes a polymeric binder and a plurality of conductive particles. A metal contact layer can then be positioned on the anisotropic conductive layer.

Abstract: A conveyor assembly for use in a vapor deposition apparatus wherein a sublimed source material is deposited as a thin film on a photovoltaic (PV) module substrate. The assembly includes a conveyor movable in an endless loop path that includes an upper leg that moves in a conveyance direction to carry a substrate through a deposition area of the vapor deposition apparatus. A heat source is disposed relative to the endless loop path so as to heat the conveyor at a location generally after the point where substrates leave the conveyor. The heat source heats the conveyor to a temperature effective for sublimating source material from the conveyor. A cold trap is disposed relative to the endless loop path downstream of the heat source in a direction of movement of the conveyor and is maintained at a temperature effective for causing sublimated source material generated from heating the conveyor to plate out onto a collection member configured with the cold trap.

Abstract: Methods for protecting a cadmium sulfide layer on a substrate are provided. The method can include sputtering a cadmium sulfide layer onto a substrate from a cadmium sulfide target at a sputtering pressure (e.g., about 10 mTorr to about 150 mTorr), and sputtering a cap layer directly on the cadmium sulfide layer. The cap layer can be sputtered directly onto the cadmium sulfide layer without breaking vacuum of the sputtering pressure. Methods are also provided for manufacturing a cadmium telluride based thin film photovoltaic device through depositing a cadmium sulfide layer on a substrate, depositing a cap layer directly on the cadmium sulfide layer, heating the substrate to sublimate at least a portion of the cap layer from the cadmium sulfide layer, and then depositing a cadmium telluride layer on the cadmium sulfide layer. An intermediate substrate for forming a cadmium telluride based thin-film photovoltaic device is also provided.

Abstract: An apparatus and related process are provided for vapor deposition of a sublimated source material as a thin film on a photovoltaic (PV) module substrate. A receptacle is disposed within a vacuum head chamber and is configured for receipt of a source material. A heated distribution manifold is disposed below the receptacle and includes a plurality of passages defined therethrough. The receptacle is indirectly heated by the distribution manifold to a degree sufficient to sublimate source material within the receptacle. A molybdenum distribution plate is disposed below the distribution manifold and at a defined distance above a horizontal plane of a substrate conveyed through the apparatus. The molybdenum distribution plate includes a pattern of holes therethrough that further distribute the sublimated source material passing through the distribution manifold onto the upper surface of the underlying substrate. The molybdenum distribution plate includes greater than about 75% by weight molybdenum.

Abstract: Methods for manufacturing a cadmium telluride based thin film photovoltaic device are generally disclosed. The method can include sputtering a resistive transparent layer on a transparent conductive oxide layer from an alloy target including zinc from about 5% by weight and about 33% by weight and tin. The method can also include forming a cadmium sulfide layer on the resistive transparent layer, forming a cadmium telluride layer on the cadmium sulfide layer, and forming a back contact layer on the cadmium telluride layer. Cadmium telluride thin film photovoltaic devices are also generally disclosed including a resistive transparent layer having a mixture of zinc oxide and tin oxide having a zinc oxide concentration between about 5% and about 33% by mole fraction.

Abstract: Apparatus and methods for testing the thermal endurance of a glass substrate of a photovoltaic module are provided. The apparatus generally includes, in one embodiment, a testing chamber defining an interior space having an interior atmosphere. A refrigeration unit is operably positioned with the testing chamber to control the interior atmosphere's temperature. A mounting system is positioned within the interior space of the testing chamber and configured to hold the photovoltaic module while exposing the glass substrate of the photovoltaic module. An edge cooling system is positioned in relation to the mounting system such that the photovoltaic module held by the mounting system has a first side edge in contact with the edge cooling system. A light system is also positioned within the interior space of the testing chamber to illuminate the glass substrate of the photovoltaic module.