PDF Publication Title:
Text from PDF Page: 016
Develop, construct and test an automated RCPCD minority-carrier lifetime mapping system (one- or two-dimensional) that incorporates auto-tuning and is capable of accepting samples up to 6” in diameter: Polycrystalline wafers and ribbons avoid the high cost of growing single crystal ingots, but non- uniformity and grain boundaries can degrade solar cell performance. Measuring the minority-carrier lifetime with spatial resolution across polycrystalline silicon can provide information toward understanding how detrimental these regions are. One of the reasons for the high cost of the commercially available microwave reflection lifetime measurement system described above is its scanning capability. Our goal was to develop a less costly scanning system with approximately the same spatial resolution of about 1 mm using the RCPCD system described above. We have designed and built a one-dimensional scanning system capable of measuring the lifetime of crystalline and multicrystalline silicon. This system (Fig. 5) is capable of rapidly analyzing heterogeneities in as-grown and processed material. The mapping capability will prove very useful in tracking and understanding the non- uniformities that are known to exist in multicrystalline silicon. Fig. 5. Lifetime Mapping System 3.4 Surface Analysis Complete experiments that correlate surface chemistry to the adhesion of polymer encapsulant and edge-seal materials used in module packaging designs. Investigate adhesion properties under both normal and damp heat conditions, with goal to facilitate 25-year module warranties: Photovoltaic R&D Fundamental Research Flexible polymer backsheet materials are being investigated as possible replacements for glass in double-glass thin-film module designs. The permeable nature of polymers, however, makes them unsuitable for long-term encapsulation. One possible solution is to deposit a thin moisture barrier on the polymer backsheet surface. The barrier efficacy is measured by its ability to impede moisture and by its adhesion to the polymer and the encapsulant. This project is jointly conducted with members of NREL’s Module Reliability team, who are investigating the use of silicon oxynitride layers on polyethylene terphthalate for such applications. The barrier films were deposited by plasma-enhanced chemical vapor deposition (PECVD) onto DuPont ST504 PET. Initial barrier results were inconsistent, and X-ray photoelectron spectroscopy (XPS) analysis found that the DuPont product had two different sides (i.e., one had been treated with an acrylic formulation, and this had not been tracked prior to the barrier depositions). A second issue was that the surface of the PET was treated with a plasma pre-etch step in the PECVD system prior to barrier layer deposition. Although initial performance of the barriers was generally good, the films on plasma- pretreated PET delaminated during damp heat testing. XPS was able to determine that failures were occurring at the PET/barrier film interface. Further, high-resolution XPS analysis from plasma-pretreated PET surfaces showed significant changes to the polymer, specifically chain scissioning with the concomitant creation of new chemical functionalities in a thin surface layer (<100 Å). Several experiments were performed to understand the stability of the reaction products. Temperature-programmed XPS was performed in which a treated PET film was heated in-situ while the photoelectron spectra for C1s, O1s, and N1s were monitored. Loss of nitrogen (N is indicative of plasma pretreatment) began at 70°C, near the polymer glass transition, with gradual restoration of the C and O signals of pure PET as the temperature was increased to the lamination temperature of 150°C. In addition, a plasma- treated film that had been water washed and transferred through inert atmosphere into the XPS also showed disappearance of the altered layer. Damp heat testing is performed at 85°C and 85% relative humidity (85/85). Our results yield a plausible explanation for loss of adhesion during damp heat testing; unstable reaction products at the PET surface create a weak interfacial layer that is affected by both temperature and humidity. Recent XPS depth profiles indicate that barrier film composition and thickness require better 10PDF Image | DOE Solar Energy Technologies Program
PDF Search Title:
DOE Solar Energy Technologies ProgramOriginal File Name Searched:
38743.pdfDIY PDF Search: Google It | Yahoo | Bing
NFT (Non Fungible Token): Buy our tech, design, development or system NFT and become part of our tech NFT network... More Info
IT XR Project Redstone NFT Available for Sale: NFT for high tech turbine design with one part 3D printed counter-rotating energy turbine. Be part of the future with this NFT. Can be bought and sold but only one design NFT exists. Royalties go to the developer (Infinity) to keep enhancing design and applications... More Info
Infinity Turbine IT XR Project Redstone Design: NFT for sale... NFT for high tech turbine design with one part 3D printed counter-rotating energy turbine. Includes all rights to this turbine design, including license for Fluid Handling Block I and II for the turbine assembly and housing. The NFT includes the blueprints (cad/cam), revenue streams, and all future development of the IT XR Project Redstone... More Info
Infinity Turbine ROT Radial Outflow Turbine 24 Design and Worldwide Rights: NFT for sale... NFT for the ROT 24 energy turbine. Be part of the future with this NFT. This design can be bought and sold but only one design NFT exists. You may manufacture the unit, or get the revenues from its sale from Infinity Turbine. Royalties go to the developer (Infinity) to keep enhancing design and applications... More Info
Infinity Supercritical CO2 10 Liter Extractor Design and Worldwide Rights: The Infinity Supercritical 10L CO2 extractor is for botanical oil extraction, which is rich in terpenes and can produce shelf ready full spectrum oil. With over 5 years of development, this industry leader mature extractor machine has been sold since 2015 and is part of many profitable businesses. The process can also be used for electrowinning, e-waste recycling, and lithium battery recycling, gold mining electronic wastes, precious metals. CO2 can also be used in a reverse fuel cell with nafion to make a gas-to-liquids fuel, such as methanol, ethanol and butanol or ethylene. Supercritical CO2 has also been used for treating nafion to make it more effective catalyst. This NFT is for the purchase of worldwide rights which includes the design. More Info
NFT (Non Fungible Token): Buy our tech, design, development or system NFT and become part of our tech NFT network... More Info
Infinity Turbine Products: Special for this month, any plans are $10,000 for complete Cad/Cam blueprints. License is for one build. Try before you buy a production license. May pay by Bitcoin or other Crypto. Products Page... More Info
CONTACT TEL: 608-238-6001 Email: greg@infinityturbine.com (Standard Web Page)