Light emission from MOS tunnel diodes

Hot carrier recombination model of visible electroluminescence from metal–oxide–silicon tunneling diodes

“…There are also reports on visible EL from MOS structures, and the origin has been attributed to oxide defects 9 and hot electrons. 10 In this letter, we report that a hot carrier recombination due to the impact ionization of the tunneling hot electron is responsible for the visible emission and the line shape of the visible emission can be fitted by this model.…”

“…The radiative recombination between tunneling electrons and accumulated holes seems unlikely re-a͒ Also at Graduate Institute of Electronic Engineering; electronic mail: chee@cc.ee.ntu.edu.tw b͒ Also at: Institute of Electro-Optical Engineering. sponsible to the visible emission, since the spectra does not change significantly in shape as the negative gate bias increases from the 5.9 to 8.7 V. 10 The energy of tunneling electrons reaching Si increases with the increasing gate voltage. The high-energy portion of the spectra would be more and more significant as the negative gate bias increases if the tunneling hot electrons recombined directly with holes.…”

“…Note that for nontransparent electrode, a special structure is needed to observe the visible light from the edge of the MOS diodes with poly Si electrodes. 10 For the ITO gate under negative bias, the electron in the ITO tunnels to the Si substrate through the thin oxide. The negative gate bias also attracts the hole at the Si/SiO 2 interface to form an accumulation region.…”

Silicon-Based Quantum Mechanical Tunnel Junction for Plasmon Excitation from Low-Energy Electron Tunneling

“…Light emission from MISJs has been studied before, − but so far all MISJ studies have used Si with low doping levels ( N d = 10 14 –10 16 cm –3 ) and only measurable amounts of light could be detected by applying large voltages (3–11 V). − ,− Although the majority of these studies claim electroluminescence from electron–hole recombination as the origin of light emission, − ,− ,− others , , disagree and claim that light emission occurs via radiative decay of SPPs excited via inelastic tunneling. It is well-known that MISJs with low doping levels result in Schottky diodes (Figure a) where the most likely mechanism for light emission involves electroluminescence from electron–hole recombination, as well as light emission from dielectric breakdown, for applied bias voltages of >2 V .…”

“…In systems dominated by thermionic emission, light emission is mainly due to electron–hole recombination, either from direct recombination of the hot electron or impact ionization where the energized electron causes a secondary electron–hole recombination during relaxation. − ,− ,− In our nSi system (where nSi represents n-doped Si), however, the current flow is from the Si (grounded) to the Au (biased) under a positive applied bias, so electron–hole recombination from thermionic emission is not favorable . However, at high enough applied bias, minority carrier injection into the Si is possible, which can lead to electron–hole recombination .…”