Donal D. C. Bradley

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We demonstrate a monolithic photonic integration platform that leverages the existing state-of-the-art CMOS foundry infrastructure. In our approach, proven XeF 2 post-processing technology and compliance with electronic foundry process flows eliminate the need for specialized substrates or wafer bonding. This approach enables intimate integration of large(More)
The nucleus tractus solitarius (NTS) in the dorsal medulla is the principal visceral sensory relay nucleus in the brain. In the rat, numerous lines of evidence indicate that the caudal NTS at the level of the area postrema serves as a major integrating site for coordinating cardiorespiratory reflexes and viscerobehavioral responses. This region of the(More)
Structures with micrometer-sized features and patterns will be useful in manipulating cells and studying the effect of mi-croenvironments on cell behavior. [1±3] This paper describes the use of patterned flows of multiple laminar streams of etching solutions in capillaries to create topographical features with sizes of 10±100 lm in poly(dimethylsiloxane)(More)
that Me-LPPP, in addition to MEH-PPV, is hole-limited with a Ca cathode. For conjugated polymer films, such as PAni, the improvement in quantum efficiency is due to an increase in the anode work function to 5.1 ± 0.1 eV, which results in a nearly ohmic contact. For nanoparticle mono-layers, the improvement is due to an increase in the local electric field(More)
Experimental LEDs were fabricated in the following manner. Indium tin oxide (ITO) sub-strates were cleaned by ultrasonication in detergent, acetone, and isopropanol. Cleaning was followed by a 5 min oxygen plasma etch at 100 W at 300 Torr of oxygen. After etching, poly(3,4-ethylenedioxythiophene) (PEDOT, Baytron P8000 from Bayer) was spin-cast at 3800 RPM(More)
Exploration of one-dimensional semiconductor nanostruc-tures has led to great progress in the areas of optoelectronics in the past few years. [1] Nanolasers, [2±4] waveguides, [5] frequency converters (second or third harmonic generators), [6] photoconductive optical switches, [7] and sensors [8,9] have been developed based on oxide nanowires. The single(More)
Devices based on solution processable organic materials are promising for inexpensive large area electronics on transparent fl exible plastic substrates. [ 1 ] In practice, however, electrodes in organic devices typically consist of vacuum deposited materials that are largely incompatible with this goal. The most widely used transparent electrode for(More)
The carrier transport of carefully purified regioregular poly(3-hexylthiophene) films has been studied using time-of-flight photocurrent measurements. We find balanced ambipolar transport with a room-temperature mobility for holes of 3 Ã 10 −4 cm 2 V −1 s −1 and for electrons of 1.5Ã 10 −4 cm 2 V −1 s −1 at electric fields ജ10 5 V / cm. The transport is(More)
riers in the 6T wire. [3] Holes are trapped by defects in the crystal, which reduces the number of mobile carriers and hinders the movement of untrapped positive-charge carriers. Charge trapping can be reversed, however, by applying a positive-gate voltage (backbiasing) to force trapped holes out of trap states via electrostatic repulsion. As seen from the(More)
The authors investigate light absorption in organic solar cells in which indium tin oxide (ITO) is replaced by a new metallic architecture (grating) as a transparent electrode. Different from typical metal nanowire gratings, our gratings consist of metal nanowalls with nanoscale footprint and (sub)microscale height [Adv. Mater. 23, 2469 (2011)], thus(More)