High‐Performance On‐Chip Thermionic Electron Micro‐Emitter Arrays Based on Super‐Aligned Carbon Nanotube Films

Abstract

An important advancement towards the realization of miniaturized and fully integrated vacuum electronic devices will be the development of on‐chip integrated electron sources with stable and reproducible performances. Here, the fabrication of high‐performance on‐chip thermionic electron micro‐emitter arrays is demonstrated by exploiting suspended super‐aligned carbon nanotube films as thermionic filaments. For single micro‐emitter, an electron emission current up to ≈20 µA and density as high as ≈1.33 A cm−2 are obtained at a low‐driven voltage of 3.9 V. The turn‐on/off time of a single micro‐emitter is measured to be less than 1 µs. Particularly, stable (±1.2% emission current fluctuation for 30 min) and reproducible (±0.2% driven voltage variation over 27 cycles) electron emission have been experimentally observed under a low vacuum of ≈5 × 10−4 Pa. Even under a rough vacuum of ≈10−1 Pa, an impressive reproducibility (±2% driven voltage variation over 20 cycles) is obtained. Moreover, emission performances of micro‐emitter arrays are found to exhibit good uniformity. The outstanding stability, reproducibility, and uniformity of the thermionic electron micro‐emitter arrays imply their promising applications as on‐chip integrated electron sources.

A monolithically sculpted van der Waals nano-opto-electro-mechanical coupler

“…And the thermionic emission onset voltage is about 3–4 V, with the maximum emission current (before the emitter channel is burnt down) at the order of 10 nA. Subthreshold swing (SS) is extracted to be at the order of 200 mV/decade, comparable with the values obtained in previously reported nanosized vacuum tubes 25 , 26 . For thermionic emission diodes, we define the ratio of maximum emission current to minimum emission current versus collector voltage at a certain V ds as an on-off ratio.…”

Fast Response GaN Nanoscale Air Channel Diodes with Highly Stable 10 mA Output Current toward Wafer‐Scale Fabrication

“…The response times of typical NACDs constructed with various materials, including Si, Metal, nanotubes, and graphene are compared in Figure 4f . [ 12 , 19 , 33 ] This highlights the fact that our GaN NACD offers response times as low as 9 ns, faster than previously reported for NACDs. Response speed can be improved further by reducing the device emission area and capacitance, as well as optimizing the electrode material and measurement setup.…”

Phonon assisted electron emission from quasi-freestanding bilayer epitaxial graphene microstructures

“…Recent advances in 2D materials have driven the emerging use of perovskites [1], carbon nanotubes (CNT), and graphene [2] in vacuum microelectronics integrated circuits. Integrated electron emission sources based around CNTs have demonstrated comparable emissions to classical thermionic sources [3] within a fraction of the footprint and power budget.…”