Proposal that interpretation of field emission current-voltage characteristics should be treated as a specialized form of electrical engineering

TL;DR

This paper argues that interpreting field emission I(V) characteristics should be approached as a specialized electrical engineering problem, addressing limitations of traditional methods and proposing a new framework called FE Systems Engineering.

Contribution

It introduces the concept of FE Systems Engineering, separating emission physics from electrostatics, and proposes new validity checks for I(V) data interpretation.

Findings

Traditional Fowler-Nordheim analysis often fails with modern materials.

A new validity check for I(V) data is proposed.

The paper defines FE Systems Engineering as a new approach.

Abstract

This article proposes that we should think differently about predicting and interpreting measured field electron emission (FE) current-voltage [I(V)] characteristics. It is commonly assumed that I(V) data interpretation is a problem in emission physics and related electrostatics. Many experimentalists then apply Fowler-Nordheim plot methodology, developed in 1929. However, with modern emitting materials this 90-year-old interpretation methodology often fails (maybe in nearly 50% of cases), and yields spurious values for characterization parameters, particularly field enhancement factors. This has generated an unreliable literature, and validity checks on experimental I(V) data are nearly always needed before use. A new check, supplementing existing checks, is described. Twelve different "system complications" that, acting singly or in combinations, can cause validity-check failure are identified. A top-level path forwards from this unsatisfactory situation is proposed. The term "field electron emission system (FE system)" is defined to include all aspects of an experimental system that affect the measured I(V) characteristics. The analysis of FE systems should now be regarded as a specialized form of electronic/electrical engineering, provisionally called "FE Systems Engineering". In this approach, the I(V) relationship is split: (a) the current is expressed as a function I(F_C) of the local surface-field magnitude F_C at some defined emitter surface location "C"; and (b) the relationship between F_C and measured voltage V is expressed and determined separately. Determining I(F_C) is mostly a problem in emission physics; determining the relationship (F_C)(V) depends on system electrostatics and (for systems failing a validity check) on other aspects of FE Systems Engineering. The scope of FE Systems Engineering, and some related research implications and problems, are outlined.