Influences of ambient gases on the emission characteristics of Nickel-deposited field emitters for vacuum microelectronics

Influences of gases on the field emission characteristics of Ni-deposited field emitters were studied by introducing O-2, Ar and N-2 gases 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 Bicker 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.