Analytical and semi-numerical models for gated FEAs

The prediction of field emitter array (FEA) device performance has been impeded by the lack of a simple methodology for comparison of disparate FEA structures. Experimental data are well characterized by the Fowler-Nordheim (FN) equation, and modeling efforts typically take advantage of this. However, numerous physical effects mitigate against simple first-principles analysis of field emission from an FEA tip, and therefore invite the question "Is FEA performance predictable?" Certain data support the notion of emission from a single, or perhaps a few, sites on a tip, in marked contrast to the idea of emission occurring continuously over a broad area. "Turn on", in which a seemingly dysfunctional tip under some subtly changing influence suddenly begins to emit, has been observed, again suggesting lack of continuity. In light of this, it appears improbable that a truly predictive and comprehensive theory or simulation analysis can he found. Before such pessimism is accepted, the fact remains that the Fowler-Nordheim characterization of experimental data is of great utility, even though the fabrication, processing, and even measurement, procedures vary widely. We must therefore ascertain what can he inferred from the experimental data through a statistical analysis.