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Oxidation and chemical modification of molybdenum micro tip surface have been investigated to understand the performance degradation mechanism of field emitter arrays(FEAs). Molybdenum FEAs could be easily oxidized due to their interaction with oxygen-containing species including O2, CO2 and H2O during cathode fabrication or thermal sealing processes of field emission displays(FEDs). During device operation, outgassing from phosphors due to electron-stimulated desorption and from other components inside a panel such as cathode, spacers, and sealant can lead to the chemical modification of the emitter surface. The oxidation and chemical modification of the emitter surface degrade the emission characteristics, resulting in the instability of an emission current, an increase of an electron extraction voltage for a given current, and lifetime reduction of the device. After the vacuum sealing and operation of the FED device, a micro tip is observed, and compared with an as-grown one by using scanning electron microscopy(SEM) and transmission electron microscopy(TEM). Chemical composition analyses of the degraded emitter surface by nano-probed Auger electron spectroscopy(AES) suggest that molybdenum micro tip is contaminated with S, In, C, and O after the device operation, where S and In seem to originate from the dissociation of phosphors by electron bombardment.

We present the discharge characteristics of a rare gas halide mixture in AC- Plasma Display Panels. Studies for excimer gas of plasma display panels are performed using XeF. This excimer gas is investigated as function of its pressure and different discharge condition. In this paper, the real panel using XeF excimer gas is researched for good discharge characteristics and a full-color panel is demonstrated.

The first 9-inch carbon nanotube based color field emission displays (FEDs) are integrated using a paste squeeze technique. The panel is composed of 576 × 242 lines with implementation of low voltage phosphors. The uniform and moving images are achieved only at 2 V/μm. This demonstrates a turning point of nanotube for large area and full color applications.

Cell gap-dependent electro-optic characteristics in the FFS mode have been studied. The operating voltage decreases with decreasing cell gap for the positive LC and response time becomes very fast with decreasing cell gap owing to increase of field intensity.

A triode structure of field emission displays based upon carbon nanotube emitters is presented. In this structure, gate electrodes are located underneath cathode electrodes with an in-between insulating layer, so called an under-gate type triode structure. The modulation of electron emission by changing gate voltages is confirmed. The advantage of simple structure and fabrication processes may lead the under-gate triode type structure to the practical applications.

Fringe-field switching device with negative liquid crystal (LC) was known to exhibit high transmittance and wide viewing angle simultaneously. Recently we have developed “Ultra-FFS” device with positive LC, exhibiting high transmittance, color shift free, high contrast ratio in wide range, no crosstalk and fast response time of 25ms. In this paper, the concept of new device will be presented.

In-situ laser sealing and annealing treatments have been performed inside a high vacuum chamber for efficient completion process of field emission displays. A high power Nd:YAG continuous wave (λ = 1,064nm) laser was mainly used as an irradiation source was used as a source. In a packaging scheme, the most vital part of the panel was kept at temperature below 300°C to shorten the entire panel process. Experimental work exhibits efficiently local hitting of frit by the laser to stitch both cathode and anode plate during the short time. In addition, laser treatment on electrophoretically deposited phosphors has been carried out as one of efficient post-annealing methods in order to improve the brightness of the phosphor coated on indium-tin oxide-coated glasses. For the annealing process, two basic parameters, such as laser power and treatment time were examined inside the same vacuum chamber. The experimental results presented useful laser-annealing time and enhanced improvement of about 10% in the brightness after the laser irradiation on the phosphor. The improvement in the brightness was thought due to the surface cleaning effect on the phosphor surface.

New emitter materials for field emission displays (FEDs) have emerged and some of them faded away. Recently, carbon nanotubes have attracted much attention as a new emitter material due to their excellent field emission characteristics. We have investigated several different structures of FEDs with carbon nanotube emitters: normal gate, remote gate, and under-gate triode structures. The panels with these structures were fabricated to be a 15″ diagonal and VGA resolution. Their field emission characteristics, uniformity, and scalability are discussed in detail.

We present the discharge characteristics of new dielectric layers in AC- plasma display panels. Studies for dielectric layer of plasma display panels are performed using CaF2. In this paper, the real panel using CaF2 dielectric layer is researched for material characteristics and discharge characteristics, and a color panel is demonstrated.

Electrophoretically deposited low voltage phosphors of FED are irradiated by electron beam from the Spindt micro tip arrays. The conditions of phosphor surface are analyzed at various conditions. Ar gas treatment is used for stabilizing the surface of ZnS:Cu,Al and ZnGa2O4:Mn with improved conditions. It is found that the electron irradiation on the phosphor seriously causes carbon effect to the phosphor surface, resulting in dark color defects on the real 4 inch FED panel. However, the contaminated phosphor surface is effectively eliminated by the gas sputtering treatment on it, and proved experimentally.

High resolution field emission display (FED) devices of 5 inch developed. Under scheme, electron diagonal in size are the gate-switching trajectory profiles fully drive are simulated and tested. Uniquely-printed spacer with high aspect ratio are fabricated on ITO coated glass for high vacuum packaging. In addition, new gas aging scheme of stabilizing field emitting array are extensively investigated during the sealing and exhausting process in order to prevent oxidation effects on the micro tip. Finally, full color images of 64 gray scale will be demonstrated.