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The Metacapacitors project aims to improve efficiency, functionality and form factor of offline power converters suitable for LED solid-state lighting, with a view to developing an attractive technology platform for load management and power conversion across a broad range of applications. Based on integrated switched-capacitor (SC) topologies, the project adopts an integrated approach from materials to devices to circuits. We designed capacitors based on high-κ dielectric nanocrystals, that can be prepared using high-throughput microfabrication/ nanotechnology techniques, ink deposition and multilayering. The capacitor dielectric, a nanocomposite composed of (Ba, Sr)TiO3 nanocrystals in polyfurfuryl alcohol (BST/PFA, κ > 20, 100Hz-1 MHz, loss < 0.01, 20 kHz), targets a high volumetric capacitance density and ripple current capability. The Dielectric is demonstrated to function in a finished capacitor >1000 h at 125°C. The capacitors were board integrated with a custom hybrid-switched-capacitor-resonant dc-dc converter IC. The converter integrates a balanced SC front-end with a series resonant tank, enabling nearly lossless current regulation and tranformerless galvanic isolation. The converter IC can be stacked in the voltage domain to interface a range of inputs. The tested driver delivers about 15 Wat 470 mA to a string of 12 LEDs with 90% peak efficiency.

A laboratory-based class in flat-panel display technology is presented. The course introduces fundamental concepts of display systems and reinforces these concepts through the fabrication of three display devices--an inorganic electroluminescent seven-segment display, a dot-matrix organic light-emitting diode (OLED) display, and a dot-matrix liquid crystal display (LCD). Instead of fabricating a device over multiple laboratory sessions, students fabricate a functional device in a single session. This approach to teaching fabrication provides students immediate results, can accommodate students with disparate backgrounds, and can be easily adapted and expanded. This paper discusses the laboratory design, its impact on student experiences, and possible improvements and extensions. (Contains 1 table and 7 figures.)

The fabrication and characterization of field emitter arrays with integrated focus is reported. A revised version of the BPM that includes quantitatively accurate closed-form expressions for the Fowler-Nordheim coefficients is resumed. Electron beam collimation, at different values of the cathode-anode separation, was also investigated.

In the path to incorporating Ge based metal-oxide-semiconductor into modern nano-electronics, one of the main issues is the oxide-semiconductor interface quality. Here, the reactivity of Ti on Ge stacks and the scavenging effect of Ti were studied using synchrotron X-ray photoelectron spectroscopy measurements, with an in-situ metal deposition and high resolution transmission electron microscopy imaging. Oxygen removal from the Ge surface was observed both in direct contact as well as remotely through an Al2O3 layer. The scavenging effect was studied in situ at room temperature and after annealing. We find that the reactivity of Ti can be utilized for improved scaling of Ge based devices. [ABSTRACT FROM AUTHOR]