Achieving very-high current density with GaN nanoscale field emitters array

On-chip nanoscale field emission devices are attractive for high-speed operation and radiation hard application due to their combined advantage of traditional vacuum tubes (e.g., high frequency operation, robustness in harsh environment) and modern solid-state technology (e.g., integrability, size, energy efficiency). However, the real-world applications of these devices are limited due to small field emission current up to few µA per device. Here we demonstrate field emission current up to several mA, with >1µA/emitter loading, in the densely packed monolithically integrated GaN lateral field emitter diodes (FED) array. We achieve current density as high as ~200A/cm² from these arrays which is the highest current density reported for semiconductor field emitters. We will present a novel approach of self-limited electron emission to enable uniform field emission across the arrays of emitters. We will also present theoretical and experimental studies on the electric field screening effect and its impact on electron emission as function of FED density.