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Si field emitter arrays (FEAs) are promising cold cathodes for field emission displays (FEDs). The emission current from the Si FEAs, however, is known to decrease significantly after the vacuum-packaging process based on the frit sealing technique. In this work, we have investigated the mechanism of the current decrease and found that CHF3plasma treatment of the tip surface was sufficiently effective to prevent the problem. In the experiment, the Si FEAs were exposed to the CHF3plasma for 15 s and then treated by the same process as that for the frit sealing at various temperatures. No changes in the emission current were observed before and after the frit sealing process at temperatures up to 430°C. Details of the CHF3plasma treatment are described.

The stability of field emission current from B-doped diamond thin films terminated with hydrogen and oxygen was measured to investigate the influence of the surface treatment and the dopant concentration on the emission stability. The diamond films were prepared by microwave plasma chemical vapor deposition. The O-termination was performed by acid cleaning in boiling chromic acid and boiling aqua regia. The H-termination was performed by exposing the above sample to hydrogen plasma. The dependence of the emission stability on the B2H6gas (dopant gas) concentration and the surface treatment was investigated. As a result, little dependence on the B concentration was observed, but dependence on the surface treatment was significant. The field emission of the H-terminated diamond thin films was confirmed to be more stable than the O-terminated films.

Low-frequency current fluctuations in nickel-deposited field emitters were evaluated quantitatively with normalized noise power which was obtained by integrating the spectral density of the current fluctuation between the frequencies of 0.2 and 2 Hz. The distance between the emitter and the collector was adjusted to 1.5 µm, in order to realize an electrode spacing similar to those of vacuum microelectronics devices. Measurements were performed under an ultrahigh-vacuum environment. The obtained noise powers were analyzed with the Seppen-Katamuki chart which indicates the effective work function and apex radius of the emitter. It was found that the emitters with higher effective work functions showed higher noise powers. The results were explained qualitatively from the differential of the Fowler-Nordheim equation.

Influences of gases on the field emission characteristics of Ni-deposited field emitters were studied by introducing O2, Ar and N2gases into a vacuum chamber. The extraction voltage depended both on the gas pressure and on the gas species. The observed noise, flicker noise and step-spike noise, was different among the gas species. For quantitative evaluations, noise power was calculated for flicker noise and the numbers of step-spike noise occurrences were counted. These quantitative evaluations allowed understanding of the origins of flicker noise depending on the emission current. By analyzing surface states of emitter apices using the slope and intercept of the Fowler-Nordheim plot (Seppen-Katamuki (S-K) chart), influences of the gases on the emitter were clarified.