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Taking the Air Out of Respiratory Pandemics: An R&D Effort for Developing New, Far Less Disruptive and Frightening Protective Measures to Extinguish Airborne Pathogen Outbreaks

Gupta, Vipin P.; Kelley, John B.

This short concept article discusses four specific ways to eradicate respiratory pandemics once and for all. These include: Protecting the nose, mouth, throat and lungs; New hygiene regimens; Clearing the air; and Biophysical interventions. Technical breakthoughs in all four of these areas would not only protect people from life-threatening pathogens, but also take the dread out of respiratory disease outbreaks.

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Microsystem Enabled Photovoltaics

Nielson, Gregory N.; Cruz Campa, Jose L.; Okandan, Murat O.; Lentine, Anthony L.; Sweatt, W.C.; Gupta, Vipin P.; Tauke-Pedretti, Anna; Jared, Bradley H.; Resnick, Paul J.; Cederberg, Jeffrey G.; Paap, Scott M.; Sanchez, Carlos A.; Biefeld, Robert M.; Langlois, Eric L.; Yang, Benjamin B.; Koleske, Daniel K.; Wierer, Jonathan J.; Miller, William K.; Elisberg, Brenton E.; Zamora, David J.; Luna, Ian L.; Saavedra, Michael P.; Alford, Charles A.; Ballance, Mark H.; Wiwi, Michael W.; Samora, S.; Chavez, Julie C.; Pipkin, Jennifer R.; Nguyen, Janet N.; Anderson, Ben A.; Gu, Tian G.; Agrawal, Gautum A.; Nelson, Jeffrey S.

Abstract not provided.

Creating Fantastic PI Workshops

Perkins, David N.; Biedermann, Laura B.; Clark, Blythe C.; Thayer, Rachel C.; Dagel, Amber L.; Gupta, Vipin P.; Hibbs, Michael R.; West, Roger D.

The goal of this SAND report is to provide guidance for other groups hosting workshops and peerto-peer learning events at Sandia. Thus this SAND report provides detail about our team structure, how we brainstormed workshop topics and developed the workshop structure. A Workshop “Nuts and Bolts” section provides our timeline and check-list for workshop activities. The survey section provides examples of the questions we asked and how we adapted the workshop in response to the feedback.

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Cost analysis of flat-plate concentrators employing microscale photovoltaic cells for high energy per unit area applications

2014 IEEE 40th Photovoltaic Specialist Conference, PVSC 2014

Paap, Scott; Gupta, Vipin P.; Tauke-Pedretti, Anna; Resnick, Paul J.; Sanchez, Carlos A.; Nielson, Gregory N.; Cruz-Campa, Jose L.; Jared, Bradley H.; Nelson, Jeffrey; Okandan, Murat O.; Sweatt, W.C.

Microsystems Enabled Photovoltaics (MEPV) is a relatively new field that uses microsystems tools and manufacturing techniques familiar to the semiconductor industry to produce microscale photovoltaic cells. The miniaturization of these PV cells creates new possibilities in system designs that can be used to reduce costs, enhance functionality, improve reliability, or some combination of all three. In this article, we introduce analytical tools and techniques to estimate the costs associated with a hybrid concentrating photovoltaic system that uses multi-junction microscale photovoltaic cells and miniaturized concentrating optics for harnessing direct sunlight, and an active c-Si substrate for collecting diffuse sunlight. The overall model comprises components representing costs and profit margin associated with the PV cells, concentrating optics, balance of systems, installation, and operation. This article concludes with an analysis of the component costs with particular emphasis on the microscale PV cell costs and the associated tradeoffs between cost and performance for the hybrid CPV design.

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Flat plate concentrators with large acceptance angle enabled by micro cells and mini lenses: performance evaluation

Cruz-Campa, Jose L.; Anderson, Benjamin J.; Gupta, Vipin P.; Tauke-Pedretti, Anna; Cederberg, Jeffrey G.; Paap, Scott M.; Sanchez, Carlos A.; Nordquist, Christopher N.; Nielson, Gregory N.; Saavedra, Michael P.; Ballance, Mark H.; Nguyen, Janet N.; Alford, Charles A.; Riley, Daniel R.; Okandan, Murat O.; Lentine, Anthony L.; Sweatt, W.C.; Jared, Bradley H.; Resnick, Paul J.; Kratochvil, Jay A.

Abstract not provided.

Advanced compound semiconductor and silicon fabrication techniques for next-generation solar power systems

ECS Transactions

Nielson, Gregory N.; Okandan, Murat O.; Cruz-Campa, Jose L.; Gupta, Vipin P.; Resnick, Paul J.; Sanchez, Carlos A.; Paap, Scott M.; Kim, B.; Sweatt, W.C.; Lentine, Anthony L.; Cederberg, Jeffrey G.; Tauke-Pedretti, Anna; Jared, B.H.; Anderson, Benjamin J.; Biefeld, Robert M.; Nelson, J.S.

Microsystem technologies have the potential to significantly improve the performance, reduce the cost, and extend the capabilities of solar power systems. These benefits are possible due to a number of significant beneficial scaling effects within solar cells, modules, and systems that are manifested as the size of solar cells decrease to the sub-millimeter range. To exploit these benefits, we are using advanced fabrication techniques to create solar cells from a variety of compound semiconductors and silicon that have lateral dimensions of 250 - 1000 μm and are 1 - 20 μm thick. These fabrication techniques come out of relatively mature microsystem technologies such as integrated circuits (IC) and microelectromechanical systems (MEMS) which provide added supply chain and scale-up benefits compared to even incumbent PV technologies. © The Electrochemical Society.

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Fabrication of lattice mismatched multijunction photovoltaic cells using 3D integration concepts

Conference Record of the IEEE Photovoltaic Specialists Conference

Cruz-Campa, Jose L.; Nielson, Gregory N.; Lentine, Anthony L.; Filatov, Anton A.; Resnick, Paul J.; Sanchez, Carlos A.; Rowen, Adam M.; Okandan, Murat O.; Gupta, Vipin P.; Nelson, Jeffrey S.

We present the experimental procedure to create lattice mismatched multijunction photovoltaic (PV) cells using 3D integration concepts. Lattice mismatched multijunction photovoltaic (PV) cells with decoupled electrical outputs could achieve higher efficiencies than current-matched monolithic devices. Growing lattice mismatched materials as a monolithic structure generates defects and decreases performance. We propose using methods from the integrated circuits and microsystems arena to produce the PV cell. The fabricated device consists of an ultrathin (6 μm) series connected InGaP/GaAs PV cell mechanically stacked on top of an electrically independent silicon cell. The InGaP/GaAs PV cell was processed to produce a small cell (750 μm) with back-contacts where all of the contacts sit at the same level. The dual junction and the silicon (c-Si) cell are electrically decoupled and the power from both cells is accessible through pads on the c-Si PV cell. Through this approach, we were able to fabricate a functional double junction PV cell mechanically attached to a c-Si PV cell with independent connections. © 2012 IEEE.

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Microfabrication of Microsystem-Enabled Photovoltaic (MEPV) cells

Proceedings of SPIE - The International Society for Optical Engineering

Nielson, Gregory N.; Okandan, Murat O.; Cruz-Campa, Jose L.; Resnick, Paul J.; Wanlass, Mark W.; Clews, Peggy J.; Pluym, Tammy P.; Sanchez, Carlos A.; Gupta, Vipin P.

Microsystem-Enabled Photovoltaic (MEPV) cells allow solar PV systems to take advantage of scaling benefits that occur as solar cells are reduced in size. We have developed MEPV cells that are 5 to 20 microns thick and down to 250 microns across. We have developed and demonstrated crystalline silicon (c-Si) cells with solar conversion efficiencies of 14.9%, and gallium arsenide (GaAs) cells with a conversion efficiency of 11.36%. In pursuing this work, we have identified over twenty scaling benefits that reduce PV system cost, improve performance, or allow new functionality. To create these cells, we have combined microfabrication techniques from various microsystem technologies. We have focused our development efforts on creating a process flow that uses standard equipment and standard wafer thicknesses, allows all high-temperature processing to be performed prior to release, and allows the remaining post-release wafer to be reprocessed and reused. The c-Si cell junctions are created using a backside point-contact PV cell process. The GaAs cells have an epitaxially grown junction. Despite the horizontal junction, these cells also are backside contacted. We provide recent developments and details for all steps of the process including junction creation, surface passivation, metallization, and release.

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Thin and small form factor cells : simulated behavior

Cruz-Campa, Jose L.; Okandan, Murat O.; Resnick, Paul J.; Grubbs, Robert K.; Clews, Peggy J.; Pluym, Tammy P.; Young, Ralph W.; Gupta, Vipin P.; Nielson, Gregory N.

Thin and small form factor cells have been researched lately by several research groups around the world due to possible lower assembly costs and reduced material consumption with higher efficiencies. Given the popularity of these devices, it is important to have detailed information about the behavior of these devices. Simulation of fabrication processes and device performance reveals some of the advantages and behavior of solar cells that are thin and small. Three main effects were studied: the effect of surface recombination on the optimum thickness, efficiency, and current density, the effect of contact distance on the efficiency for thin cells, and lastly the effect of surface recombination on the grams per Watt-peak. Results show that high efficiency can be obtained in thin devices if they are well-passivated and the distance between contacts is short. Furthermore, the ratio of grams per Watt-peak is greatly reduced as the device is thinned.

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Back-contacted and small form factor GaAs solar cell

Cruz-Campa, Jose L.; Nielson, Gregory N.; Okandan, Murat O.; Sanchez, Carlos A.; Resnick, Paul J.; Clews, Peggy J.; Pluym, Tammy P.; Gupta, Vipin P.

We present a newly developed microsystem enabled, back-contacted, shade-free GaAs solar cell. Using microsystem tools, we created sturdy 3 {micro}m thick devices with lateral dimensions of 250 {micro}m, 500 {micro}m, 1 mm, and 2 mm. The fabrication procedure and the results of characterization tests are discussed. The highest efficiency cell had a lateral size of 500 {micro}m and a conversion efficiency of 10%, open circuit voltage of 0.9 V and a current density of 14.9 mA/cm{sup 2} under one-sun illumination.

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Back contacted and small form factor GAAS solar cell

Cruz-Campa, Jose L.; Nielson, Gregory N.; Okandan, Murat O.; Sanchez, Carlos A.; Resnick, Paul J.; Clews, Peggy J.; Pluym, Tammy P.; Gupta, Vipin P.

We present a newly developed microsystem enabled, back-contacted, shade-free GaAs solar cell. Using microsystem tools, we created sturdy 3 {micro}m thick devices with lateral dimensions of 250 {micro}m, 500 {micro}m, 1 mm, and 2 mm. The fabrication procedure and the results of characterization tests are discussed. The highest efficiency cell had a lateral size of 500 {micro}m and a conversion efficiency of 10%, open circuit voltage of 0.9 V and a current density of 14.9 mA/cm{sup 2} under one-sun illumination.

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Results 1–50 of 55
Results 1–50 of 55