Statistical analysis of field emitter emissivity: application to flat displays

A new type of field emitter diagnostics has been developed, which takes into account a normal distribution of microtip sharpness. Substantial curvature in the Fowler-Nordheim plot is predicted at very low voltages and currents. From this curvature it is possible to calculate the mean and standard deviation of tip sharpness as well as other parameters relating to the voltage dependence of microtip sharpness. Thirteen Fowler-Nordheim plots are made with three anode voltages and six field emitter display (FED) panels fabricated at Pixel/LETI. Each of the FEDs has about 200 million Spindt-type microtips. Comparison between theory and experiment shows good agreement. The ratio of standard deviation to mean tip sharpness is about 10% for all panels tested. Noise-free measurements are made with very low average currents in the range of 10-16-10-11 A/tip.