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Oxide films of the quality required for the fabrication of electronic and photonic devices are typically deposited at elevated temperatures and thermal equilibrium, thereby adversely impacting thermal budgets. We report the deposition and patterning of silicon dioxide (SiO2) films of high electrical and optical quality on Si(100) or polymer substrates in a N2 atmosphere and at 300 K by the photochemical conversion of thin liquid tetraethoxysilane (TEOS) layers with narrowband vacuum ultraviolet radiation [vacuum ultraviolet (VUV), 172 nm] provided by efficient microplasma lamps. Irradiating liquid TEOS layers, produced by spin-coating the precursor onto a substrate, with a VUV intensity of 13 mW cm−2, yields 40 nm-thick SiO2 films having a dielectric breakdown strength (Eb) of 5 MV cm−1, for which no precedent exists in the deposition of oxide films at 300 K. If room temperature-deposited films are post-annealed at 200 °C, Eb rises to 7.5 MV cm−1, which is <12% below the measured value (8.5 MV cm−1) for 40 nm SiO2 films grown by thermal oxidation. The deposition of 1 µm thick, stoichiometric SiO2 films requires only 20 min of VUV illumination at low optical fluences, and films with thicknesses of ∼35–60 nm exhibit a refractive index of 1.45 (633 nm). X-ray photoelectron spectrometry and Rutherford backscattering analysis indicate that, despite the deposition temperature, hydrocarbon impurity levels are near or below the detection limit. The capability for depositing 960 nm-thick SiO2 films uniformly (to within 0.6%) by liquid → solid photochemical conversion over a 5 cm diameter Si substrate and patterning films onto flexible polymer substrates has also been demonstrated. [ABSTRACT FROM AUTHOR]

Adaptation of wet chemical processing or replica molding techniques to microcavity plasma device technology has yielded lightweight and flexible arrays in the Al/[Al.sub.2][O.sub.3] materials system and plastic substrates, respectively. Microplasma arrays fabricated from two bonded sections of Al mesh with an integral dielectric barrier of nanoporous alumina have an overall thickness of < 100 [micro]m, resulting in lamps that are flexible and conformable to a variety of surfaces. Operating these arrays in both flat and curved configurations reveals few changes to the voltage-current characteristics but a reduction of a factor of two in the luminance of curved or bent structures relative to that for a flat array. Truncated paraboloid cavities have also been formed in 30-70-[micro]m-thick Al foil by a sequence of wet chemical processes. Microcavities with an emitting aperture diameter as small as 50 [micro]m have been realized, and arrays comprising [10.sup.4] cavities exhibit ignition voltages of ~140-150 V (rms) for Ne pressures between 400 and 700 torr and a 20-kHz sinusoidal voltage waveform. Mixtures of Ne and Xe with Xe content up to 67% have been operated successfully. Ignition voltages of only 70-90 V (rms) have been measured for 30 x 30 arrays of 200 x 200-[micro][m.sup.2] microcavities formed in ultraviolet curable polymer by replica molding and operating in 400-600 torr of Ne. For 3% [N.sub.2]/Ar mixtures at total pressures of 400-700 torr, the ignition voltages rise to ~150-220 [V.sub.RMS] for a driving frequency of 20 kHz, the array emission is spatially uniform, and rms currents above 85 mA can be drawn in the steady state by these plastic-based arrays. Index Terms--Atmospheric plasmas, microplasma arrays, microplasmas.

The fabrication of lightweight and optically transparent arrays of microplasma devices having microcavities fabricated by a polymer-based replica molding process is reported. This process enables arrays of microcavity plasma devices and connecting channels with feature sizes as small as 20 J. [micro]m to be produced inexpensively and precisely over surface areas of at least tens of square centimeters. Devices having transparent electrodes and substrates (including glass and flexible plastic) have been operated successfully at rare gas pressures up to 700 torr. Individual microplasma pixels with cross-sectional dimensions of 200 x 200 [micro][m.sup.2] and 50 x 50 [micro][m.sup.2], as well as plasma channels having widths of 20 and 150 [micro]m and aspect ratios (channel length : width) as large as [10.sup.4]:1, have been fabricated and tested. Representative voltage-current data for these structures and lifetime measurements for a 20 x 20 pixel array are presented. [2006-0099] Index Terms--Flexible display, microcavity plasmas, replication process, transparent display.

A two-dimensional fluid simulation of microplasmas is used to study the ac-driven cylindrical microactivity plasma devices. The analysis reveals that an annular discharge can be easily produced by increasing the gas pressure, which in turn leads to a negative glow in the vicinity of the microcavity wall.

In this paper, we report the development of hollow-cathode micro plasma devices made using micromachining techniques. Compared with larger discharge devices, micromachined discharge devices operate at much higher pressures, up to 1 atm. Linear current-voltage relationships are obtained, potentially simplifying the control electronics for such devices. The size of micromachined discharge units is reduced and the distribution of sizes and light intensity in an array is more uniform relative to previous devices. [721] Index Terms--Hollow cathode, microdischarge, micromachine.

The output power of the green lambda nearly equal to 549 nm holonium-doped fluorozirconate glass (ZBLAN) fiber laser, is a function of the absorbed pump power and fiber length. The output power, temporal and tuning characteristics of the green ZBLAN are studied with fiber laser pumped in the red, with lambda nearly equal to 643 nm. The slope efficiency and wide tunability of this fiber laser are suitable for applications that need green radiation.