| Displays based on the principles of field emission hold a promising future for the emergence of next generation flat panel displays. A field emission display (FED) combines performance of a cathode ray tube (CRT) in the configuration of a flat panel display, such as power efficiency, high brightness and resolution, wide viewing angles, light weight, tolerance to temperature changes, and instant operation. However, their commercial application has been delayed because of the complex sub-micron processing involved in the fabrication of microtips for the cathode, early failure of cathodes due to sputter damage from uncontrolled emission current or current runoff, non-availability of blue phosphors operating in low voltage regimes, and lack of optimum sealing conditions.; The primary focus of this research was towards the development of a monochromatic monolithic thin-film edge emitter (MT-FEE) device while implementing a blue light emitting phosphor of zinc oxide and tungsten. The device design reported here overcomes the above-mentioned drawbacks of the conventional FED designs. Employing a two-layer photoresist technology, the successful fabrication of devices and emission of blue light at voltages as low as 270 volts were demonstrated.; Also, this work attempted to understand the performance of the MT-FEE devices by controlling key parameters associated with the technology. In particular, an effort was made to characterize the DC diode performance of the devices based upon inter-electrode spacing, cathode design, and number of emitters. Several test structures were fabricated by varying the dielectric separating anode and cathode lines, from 3–6 μm with emitter geometries as either saw-teeth or rectangular edges. Stable emission currents of approximate value 200 nA and 20 nA per pixel were obtained at voltages as low as 300 volts for 3 μm and 6 μm devices respectively. Blue light was visible to naked eyes from several excited pixels in the 3 μm devices while it was difficult to see emitted blue light from the 6 μm. It is possible to further improve the performance of the devices with advanced microfabrication techniques available on a commercial scale. There is, however, a further need to consider triode structures based upon this technology to reduce operating voltages further while increasing emission currents. |
