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

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 approximate to 20 mu A and density as high as approximate to 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 mu s. 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 approximate to 5 x 10(-4) Pa. Even under a rough vacuum of approximate to 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.