Abstract: Processes of identifying small pressure irregularities in a system used for continuous plasma deposition are provided. Sensitive light scattering is used to detect the presence of nucleated particles in a detection area that is outside the plasma region of high electric field whereby the presence of the particles indicates a pressure abnormality in the plasma deposition chamber. The pressure of the plasma deposition chamber is then adjusted to reduce or eliminate the presence of particles within the detection area and to optimize deposition of material on a substrate.

Abstract: A process for detecting and terminating a fault in a photovoltaic device is provided that operates in the millisecond or faster timescale. A process includes measuring a current or voltage in each of a plurality of strings relative to a common rail. When the voltage or current from a string is outside a predetermined threshold, a flag is generated indicating the presence of a fault in the string. A control unit will detect the flag and disconnect the faulty string from the system through a switch. The use of continuously rolling averages of baseline currents and voltages as well as a series of measurements averaged to measure the difference of current or voltage at each step provides a process and a fault detection system that does not suffer from false fault detections thereby providing a reliable and efficient system for detecting and terminating faults in photovoltaic devices.

Abstract: A photovoltaic device and processes of manufacture are provided that employ particularly configured, textured back reflector structures that maintain a smooth, non-textured surface at the interface between the lowermost doped layer of semiconductor material and the intrinsic, light absorbing layer of nanocrystalline semiconductor material. The back reflector structure provides exhibit both superior short circuit current and a superior fill factor to a photovoltaic device such as those using nanocrystalline semiconductor materials.

Abstract: A pinch valve assembly includes a valve body having a slot which is configured to allow a web of substrate material to pass therethrough. The valve body has a sealing surface which includes a first curved portion with a first radius of curvature. A dynamic seal element is configured to engage the valve body and includes a second curved portion having a second radius of curvature which is larger than the first radius of curvature. An actuator is operable to selectively bias the dynamic seal element into and out of engagement with the valve body so that when it is biased into engagement with the valve body the web of substrate material is engaged between the sealing surfaces of the dynamic seal element and the valve body. Also disclosed are deposition systems which include these pinch valves.

Abstract: A continuous roll-to-roll apparatus for providing a patterned deposit of a material onto a moving substrate web includes a payout station for feeding out a substrate web, a take-up station for taking up the substrate web, and a web transport system for advancing the web through the apparatus from the payout station to the take-up station. The apparatus includes at least one deposition station disposed between the payout station and the take-up station, and the deposition station is operative to deposit a material onto the web as it moves therethrough. The apparatus includes a masking system associated with a deposition station. The masking system is operative to dispose a deposition mask in registry with a portion of the length of the moving web. The deposition mask is comprised of a plurality of filaments which are aligned with the longitudinal axis of the web.

Abstract: A photovoltaic module comprised of a plurality of series connected photovoltaic cells disposed upon a substrate is fabricated utilizing thin film device techniques. A body of photovoltaic stock material comprised of an electrically conductive substrate having at least a bottom electrode layer, a body of photovoltaic material, and a top electrode layer supported thereupon is patterned so as to define a number of individual, electrically isolated photovoltaic cells and a number of electrically isolated connection zones. The connection zones are patterned to each include a portion of the bottom electrode material and are configured so that the bottom electrode material in each segment of the connection zone is exposed, and is in electrical communication with the bottom electrode portion of a particular cell.

Abstract: A bus grid structure is affixed to a photovoltaic device utilizing a double-sided adhesive tape in which one of the adhesive layers is electrically conductive and the other is electrically resistive. The tape is affixed to a photovoltaic device via the electrically resistive adhesive. Grid wires are applied to a top electrode of the photovoltaic device, and portions of those grid wires are adhered to the electrically conductive adhesive. A bus bar is also adhered to the electrically conductive adhesive so as to contact the portions of the grid wire. The assembly is laminated so as to bond the grid wires to the photovoltaic device and to the bus bar. Further disclosed are devices fabricated according to this method as well as electrically conductive double adhesive tapes utilized in the process.

Abstract: A system and method for measuring the velocity of gas flow between multiple plasma deposition chambers is provided. A passage atmospherically linking two plasma processing chambers conducts a gas flow therebetween due to differential pressures within the respective chambers. The gas flow velocity is measured by a linear or non-linear ultrasonic energy acoustic path between two transducers located exteriorly to the chambers using the difference in transit time in a forward and reverse direction due to the velocity of gas in the passage. The pressure of process gas in one or more chambers is adjustable based on the measured velocity of gas flow in the passage.

Abstract: A tandem photovoltaic device includes at least two photovoltaic cells stacked in an optical and electrical series relationship. At least one of the tandem cells includes a dual function semiconductor layer fabricated from a dual function semiconductor material. This dual function layer is an electronically active constituent of the cell. The dual function layer also is optically active and creates a reflective condition which redirects a portion of the light which has passed through the cell back through the cell's active layers to photo generate additional photocurrent. Use of the dual function material eliminates the need for incorporating separate semiconductor and reflective layers in a photovoltaic device. Further disclosed are exemplary formulations of some dual function materials.

Abstract: A reverse interferometric method for the determination of the thickness of a layer of material employs a multi-wavelength light source which generates a light beam which comprises a time-variant series of different monochromatic wavelengths. The beam is reflected from the body of material being measured and is detected by a broad spectrum wavelength detector which produces a signal comprising a series of data points indicating the reflectivity of the sample as a function of the time-variant series of monochromatic wavelengths. A signal processor processes these data points to fit them to a model waveform, and the frequency of the model waveform is used to calculate the thickness of the body of material. Further disclosed are apparatus for carrying out the method and use of the method in a continuous process for the fabrication of thin film materials.

Abstract: A system for the laser scribing of semiconductor devices includes a laser light source operable to selectably deliver laser illumination at a first wavelength and at a second wavelength which is shorter than the first wavelength. The system further includes a support for a semiconductor device and an optical system which is operative to direct the laser illumination from the light source to the semiconductor device. The optical system includes optical elements which are compatible with the laser illumination of the first wavelength and the laser illumination of the second wavelength. In specific instances, the first wavelength is long wavelength illumination such as illumination of at least 1000 nanometers, and the second wavelength is short wavelength illumination which in specific instances is 300 nanometers or shorter. By the use of the differing wavelengths, specific layers of the semiconductor device may be scribed without damage to subjacent layers. Also disclosed are specific scribing processes.

Abstract: A web of a first sheet material and a web of a second sheet material are laminated together by a process wherein the sheet materials are wound, in an interleaved relationship, upon a roller having a radially displaceable outer surface. The roller and webs and then subjected to heating and/or a low-pressure environment so as to complete the lamination. A body of adhesive material, such as a hot melt adhesive, may be interposed between the webs and the heating or low pressure environment can activate this adhesive. Further disposed are particular configurations of rollers with radially displaceable surfaces.

Abstract: A method for passivating short circuit defects in a thin film large area photovoltaic device in accordance with an exemplary embodiment is provided. The method employs a passivation agent and a counter electrode disposed in said passivation agent. The method includes controlling an application of current between the substrate of said photovoltaic device and said counter electrode so as to ensure high selectivity of modification of a transparent conductive oxide material of said photovoltaic module adjacent said short circuit defect, while leaving the transparent conductive oxide material of said photovoltaic module of non-defect areas in its unmodified form.

Abstract: A process for the plasma deposition of a layer of a microcrystalline semiconductor material is carried out by energizing a process gas which includes a precursor of the semiconductor material and a diluent with electromagnetic energy so as to create a plasma therefrom. The plasma deposits a layer of the microcrystalline semiconductor material onto the substrate. The concentration of the diluent in the process gas is varied as a function of the thickness of the layer of microcrystalline semiconductor material which has been deposited. Also disclosed is the use of the process for the preparation of an N-I-P type photovoltaic device.

Abstract: A system for the continuous deposition of a semiconductor material onto one or more webs of substrate material which are advanced therethrough includes a web transport system having a plurality of web support assemblies. Each web support assembly includes a base having a primary support arm pivotally mounted thereto so as to be displaceable from a first position to a second position. The support includes a first biasing member in mechanical communication with the primary support arm. The first biasing member operates to impart a first biasing force to the primary support arm so as to move it from its first position to its second position. The support includes a dancer arm which is pivotally mounted to the primary support arm so as to be displaceable from a first position to a second position relative to the primary support arm. The system further includes a second biasing member in mechanical communication with the dancer arm.

Abstract: A web support assembly for a moving web of substrate material includes a base having a primary support arm pivotally mounted thereto so as to be displaceable from a first position to a second position. The web support assembly includes a first biasing member in mechanical communication with the primary support arm. The first biasing member operates to impart a first biasing force to the primary support arm so as to move it from its first position to its second position. The system includes a dancer arm which is pivotally mounted to the primary support arm so as to be displaceable from a first position to a second position relative primary support arm. The web support assembly further includes a second biasing member in mechanical communication with the dancer arm. The second biasing member operates to impart a second biasing force to the dancer arm so as to move it from its first position to its second position. A roller is rotatably supported on the dancer arm.

Abstract: A pinch valve includes a valve body having a slot which is configured to allow a web of substrate material to pass therethrough. The valve body has a sealing surface which includes a first curved portion with a first radius of curvature. A dynamic seal element is configured to engage the valve body and includes a second curved portion having a second radius of curvature which is larger than the first radius of curvature. An actuator is operable to selectively bias the dynamic seal element into and out of engagement with the valve body so that when it is biased into engagement with the valve body the web of substrate material is engaged between the sealing surfaces of the dynamic seal element and the valve body. Also disclosed is a processing system which includes the pinch valve.

Abstract: A pinch valve includes a valve body having a slot which is configured to allow a web of substrate material to pass therethrough. The valve body has a sealing surface which includes a first curved portion with a first radius of curvature. A dynamic seal element is configured to engage the valve body and includes a second curved portion having a second radius of curvature which is larger than the first radius of curvature. An actuator is operable to selectively bias the dynamic seal element into and out of engagement with the valve body so that when it is biased into engagement with the valve body the web of substrate material is engaged between the sealing surfaces of the dynamic seal element and the valve body. Also disclosed is a processing system which includes the pinch valve.

Abstract: A metal and oxygen material such as a transparent electrically conductive oxide material is electro deposited onto a substrate in a solution deposition process. Process parameters are controlled so as to result in the deposition of a high quality layer of material which is suitable for use in a back reflector structure of a high efficiency photovoltaic device The deposition may be carried out in conjunction with a masking member which operates to restrict the deposition of the metal and oxygen material to specific portions of the substrate. In particular instances the deposition may be implemented in a continuous, roll-to-roll process. Further disclosed are semiconductor devices and components of semiconductor devices made by the present process, as well as apparatus for carrying out the process.

Abstract: Disclosed herein is a method of making a photovoltaic device having a protective layer affixed to a top surface thereof. The protective layer is comprised of a polymeric material having a fluorinated first surface and a second, opposed, surface which is non-fluorinated or less fluorinated. The protective layer is affixed to the photovoltaic device so that the first surface is farthest therefrom. In some instances, the fluorination may extend to edge portions of the protective layer as well as to any intermediate layers. Further disclosed are devices which incorporate the fluorinated protective layers.