Improvement of the emission current from a cesiated metal-oxide-semiconductor cathode

Abstract

We have reduced the work function of the gate electrode of a metal-oxide-semiconductor tunneling cathode by cesiation. After cesiation, there was a considerable increase in the emission current and a large number of electrons were detected at energies lower than the original vacuum level of the poly-Si gate electrode. These results indicate that almost all the tunneling electrons have energies lower than the original vacuum level of the gate electrode, and that after cesiation electrons initially prevented from being emitted by the original vacuum level were emitted, because of the reduced work function due to cesiation.

Development of dry-processed silicon nanodot planar cold cathode and its electron emission properties

“…The energy distribution at the V d of 26 V ͑at the electric field of about 4 ϫ 10 6 V / cm͒ is much broader than that at a comparable electric field in the metal-oxide-semiconductor ͑MOS͒ cold cathodes reported previously. [11][12][13] The broad distributions are similar to those of quasiballistic electrons observed in the planar-type porous Si cold cathodes. 2,4,14 The peak energy shifts from 2.1 to 2.9 eV with increasing V d from 22 to 30 V. As compared with the typical case in the porous Si cold cathodes, 2,4 the V d dependence is smaller and the peak energies are lower.…”

Freestanding membrane composed of micro-ring array with ultrahigh sidewall aspect ratio for application in lightweight cathode arrays

“…In our experiment, the IM cathode contains a silica layer and a gold layer. IM cathodes have been widely reported as a promising cathode due to their nearly fluctuation-free emission current, emission uniformity, highly directional electron beam and inherent insensitivity for surface contamination [26][27][28]. For the IM cathode, when a gate voltage V g is applied between the base electrode and top electrode, the electrons emitted from the gold sharp edge will inject into the vacuum space and be accelerated by the high electric field.…”

Monochromatic electron-emission from planar AlN/GaN multilayers with carbon nanotube gate electrode

“…They demonstrate reduced failure and increased lifetime compared with nanostructured emitters. a) Author to whom correspondence should be addressed; electronic mail: yilmazoglu@hfe.tu-darmstadt.de Initial results from metal-oxide-semiconductor cathodes were published by Mimura et al 16 These emitters present advantages such as low operating voltage (<10 V), fluctuationfree emission current, uniform emission from whole emitter area, highly directional electron beam, and large degree of independence from ambient gas pressure. The drawbacks are scattering in the oxide layer and metal gate electrode, wider electron energy distribution, large gate (diode) current, and low emission efficiency.…”

“…These properties improve the drawbacks of the metal-oxide-semiconductor cathode. 16 GaN is also a direct bandgap material, which can act as a photosensitive electron emitter. A laser-assisted emission is possible by integration of a light absorption layer before the resonant tunneling layers.…”