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Emerging classes of concentrator photovoltaic (CPV) modules reach efficiencies that are far greater than those of even the highest performance flat-plate PV technologies, with architectures that have the potential to provide the lowest cost of energy in locations with high direct normal irradiance (DNI). A disadvantage is their inability to effectively use diffuse sunlight, thereby constraining widespread geographic deployment and limiting performance even under the most favorable DNI conditions. This study introduces a module design that integrates capabilities in flat-plate PV directly with the most sophisticated CPV technologies, for capture of both direct and diffuse sunlight, thereby achieving efficiency in PV conversion of the global solar radiation. Specific examples of this scheme exploit commodity silicon (Si) cells integrated with two different CPV module designs, where they capture light that is not efficiently directed by the concentrator optics onto large-scale arrays of miniature multijunction (MJ) solar cells that use advanced III-V semiconductor technologies. In this CPV+ scheme ("+" denotes the addition of diffuse collector), the Si and MJ cells operate independently on indirect and direct solar radiation, respectively. On-sun experimental studies of CPV+ modules at latitudes of 35.9886° N (Durham, NC), 40.1125° N (Bondville, IL), and 38.9072° N (Washington, DC) show improvements in absolute module efficiencies of between 1.02% and 8.45% over values obtained using otherwise similar CPV modules, depending on weather conditions. These concepts have the potential to expand the geographic reach and improve the cost-effectiveness of the highest efficiency forms of PV power generation.

Compound semiconductors like gallium arsenide (GaAs) provide advantages over silicon for many applications, owing to their direct bandgaps and high electron mobilities. Examples range from efficient photovoltaic devices (1,2) to radio-frequency electronics (3,4) and most forms of optoelectronics (5,6). However, growing large, high quality wafers of these materials, and intimately integrating them on silicon or amorphous substrates (such as glass or plastic) is expensive, which restricts their use. Here we describe materials and fabrication concepts that address many of these challenges, through the use of films of GaAs or AlGaAs grown in thick, multilayer epitaxial assemblies, then separated from each other and distributed on foreign substrates by printing. This method yields large quantities of high quality semiconductor material capable of device integration in large area formats, in a manner that also allows the wafer to be reused for additional growths. We demonstrate some capabilities of this approach with three different applications: GaAs-based metal semiconductor field effect transistors and logic gates on plates of glass, near-infrared imaging devices on wafers of silicon, and photovoltaic modules on sheets of plastic. These results illustrate the implementation of compound semiconductors such as GaAs in applications whose cost structures, formats, area coverages or modes of use are incompatible with conventional growth or integration strategies., Some of the most daunting technical challenges associated with established methods for using GaAs occur in terrestrial photovoltaics, where the extremely high efficiencies of GaAs solar cells (7,8) might otherwise [...]

The promise of organic electronics and optoelectronics could be realized only when the efforts are put to develop low-cost, large area printing, like manufacturing techniques which are successful. Work in this area is reviewed with an emphasis on the method that is successfully applied to the fabrication of working organic devices.

A procedure for fabricating flexible forms of high electron mobility transistors (HEMTs) supported on plastic substrates is described. The process uses a combination of conventional top-down, wafer scale fabrication protocols to define a printable form of ultrathin, device quality multilayer AlGaN/GaN single crystalline microstructures—a so-called microstructured semiconductor ink—and soft-lithographic printing methods to effect their registered transfer to a plastic substrate. These procedures yield high performance, bendable HEMT arrays that are mechanically durable—ones with effective transconductances exceeding nearly all reported forms of printed thin-film transistors. [ABSTRACT FROM AUTHOR]

A new technique, which makes use of a combination of conventional top-down, wafer scale fabrication protocols for the fabrication and production of bendable and flexible GaN high electron mobility transistors (HEMTs) supported on plastic substrates is presented. An analysis of the technique reveals that the methodology yields extremely high performance and mechanically durable HEMT arrays, which can be used widely for the development of next generation macroelectronic circuits.

Emerging classes of concentrator photovoltaic (CPV) modules reach efficiencies that are far greater than those of even the highest performance flat-plate PV technologies, with architectures that have the potential to provide the lowest cost of energy in locations with high direct normal irradiance (DNI). A disadvantage is their inability to effectively use diffuse sunlight, thereby constraining widespread geographic deployment and limiting performance even under the most favorable DNI conditions. This study introduces a module design that integrates capabilities in flat-plate PV directly with the most sophisticated CPV technologies, for capture of both direct and diffuse sunlight, thereby achieving efficiency in PV conversion of the global solar radiation. Specific examples of this scheme exploit commodity silicon (Si) cells integrated with two different CPV module designs, where they capture light that is not efficiently directed by the concentrator optics onto large-scale arrays of miniature multijunction (MJ) solar cells that use advanced III-V semiconductor technologies. In this CPV+ scheme ("+" denotes the addition of diffuse collector), the Si and MJ cells operate independently on indirect and direct solar radiation, respectively. On-sun experimental studies of CPV+ modules at latitudes of 35.9886° N (Durham, NC), 40.1125° N (Bondville, IL), and 38.9072° N (Washington, DC) show improvements in absolute module efficiencies of between 1.02% and 8.45% over values obtained using otherwise similar CPV modules, depending on weather conditions. These concepts have the potential to expand the geographic reach and improve the cost-effectiveness of the highest efficiency forms of PV power generation. [ABSTRACT FROM AUTHOR]

Displays that use direct light emission from microscale inorganic light emitting diodes (ILEDs) have the potential to be very bright and also very power efficient. High-throughput assembly technologies that accurately and cost-effectively deposit large arrays of ILEDs onto display substrates with high yield are key enablers for ILED displays. Transfer-printing with elastomer stamps is a candidate assembly technology for making ILED displays. A variety of passive matrix ILED displays have been designed and fabricated using transfer-printed microscale ILEDs. [ABSTRACT FROM AUTHOR]