Electron microscopy studies of near-surface layers of ZrO2(Y)-Al2O3 composite ceramic modified by high-current beam of low-energy electrons

Abstract In 1925 Pierre Auger reported on his observations of low energy electrons associated with core-ionised atoms in cloud chamber experiments. He was able to correctly identify the mechanism for their production, and such electrons are now known as Auger electrons. Typically Auger electrons have energies in the range 10 eV to 2 keV. The short distance that such low energy electrons travel in solids ensures that Auger electrons come from the surface layers. The data generated by the AES technique are complex. There are at least three electrons involved in the process, and there are many possible configurations for the atom. These possibilities led to spectra that are not readily interpreted in detail. Theory lags behind experiment in this area. In principle, it should be possible to find information about the chemical environment of atoms from Auger spectra. While there are clear changes in spectral lineshapes, there is no simple way to go from the spectra to an understanding of the chemical bonding of the atom. There are a number of experiments currently underway which aim to improve our understanding of the Auger process. Synchrotron experiments with tunable energy x-rays are providing new insight. Experiments that use positrons to excite Auger emission have also produced further recent understanding. Coincidence experiments between photoelectrons and Auger electrons have also made recent advances. Auger photoelectron coincidence spectroscopy reduces the complexity of Auger spectra by only counting those electrons that occur as a consequence of selected ionisations. The effect is to reduce the complexity of the spectra, and to isolate processes that are often clouded by the simultaneous occurrence of other effects.

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Neutralization of space charge on high-current low-energy ion beam by low-energy electrons supplied from silicon based field emitter arrays

10.1063/1.4766565 ◽

2012 ◽

Cited By ~ 5

Author(s):

Yasuhito Gotoh ◽

Hiroshi Tsuji ◽

Shuhei Taguchi ◽

Keita Ikeda ◽

Takayuki Kitagawa ◽

...

Keyword(s):

Space Charge ◽

Ion Beam ◽

Low Energy ◽

High Current ◽

Field Emitter ◽

Field Emitter Arrays ◽

Low Energy Electrons ◽

Silicon Based

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Threshold Energy Effects in Secondary Electron Emission

Microscopy and Microanalysis ◽

10.1007/s100050010042 ◽

2000 ◽

Vol 6 (4) ◽

pp. 291-296

Author(s):

A. Howie

Keyword(s):

Electron Microscopy ◽

Secondary Electron Emission ◽

Threshold Energy ◽

Environmental Scanning Electron Microscopy ◽

Low Energy ◽

Environmental Scanning ◽

Scanned Probe Microscopy ◽

Low Energy Electrons ◽

Bandgap Semiconductors ◽

Threshold Energies

Abstract In large bandgap semiconductors and insulators, the threshold energies for e–h pair production and ionization damage can lie above the vacuum level. For low energy imaging, a window is then opened whose width is potentially sensitive to local changes in work function, doping level, or acidity. Recent progress and future opportunities for damage-free imaging of these properties using low energy electrons are discussed in the light of the underlying physics, as well as of recent instrumental developments in low energy electron microscopy (LEEM), environmental scanning electron microscopy (ESEM), photoelectron emission microscopy (PEEM), scanned probe microscopy (SPM), and projection electron microscopy.

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Production and application of low-energy, high-current electron beams

Laser and Particle Beams ◽

10.1017/s0263034603212040 ◽

2003 ◽

Vol 21 (2) ◽

pp. 157-174 ◽

Cited By ~ 120

Author(s):

G.E. OZUR ◽

D.I. PROSKUROVSKY ◽

V.P. ROTSHTEIN ◽

A.B. MARKOV

Keyword(s):

Electron Beams ◽

Low Energy ◽

Nonstationary Temperature ◽

High Current ◽

Surface Layers ◽

Explosive Emission ◽

Energy Density Distribution ◽

Structure Phase ◽

Current Electron ◽

High Current Electron

This article reviews experiments on the production of low-energy, high-current electron beams (LEHCEB) and their use for surface modification of materials. It is shown that electron guns with a plasma anode and an explosive emission cathode are most promising for the production of this type of beams. The problems related to the initiation of explosive emission and the production and transportation of LEHCEBs in plasma-filled diodes are considered. It has been shown that if the rise time of the accelerating voltage is comparable to or shorter than the time it takes for an ion to fly through the space charge layer, the electric field strength at the cathode and the electron current density in the layer are increased. Experimentally, it has been established that the current of the beam transported in the plasma channel is 1–2 orders of magnitude greater than the critical Pierce current and several times greater than the chaotic current of the anode plasma electrons. Methods for improving the uniformity of the energy density distribution over the beam cross section are described. The nonstationary temperature and stress fields formed in metal targets have been calculated. The features of the structure-phase transformations in the surface layers of materials irradiated with LEHCEBs have been considered. It has been demonstrated that in the surface layers quenched from the liquid state, nonequilibrium structure-phase states are formed.

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The Effect of Low-Energy Electron and Ion Beams on Properties of Near Surface Layers in Semiconductor Crystals

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.6-7.409 ◽

1989 ◽

Vol 6-7 ◽

pp. 409-410

Author(s):

Eugene B. Yakimov

Keyword(s):

Ion Beams ◽

Low Energy ◽

Energy Electron ◽

Surface Layers ◽

Near Surface ◽

Semiconductor Crystals ◽

Low Energy Electron

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Threshold Energy Effects in Secondary Electron Emission

Microscopy and Microanalysis ◽

10.1017/s1431927602000521 ◽

2000 ◽

Vol 6 (4) ◽

pp. 291-296 ◽

Cited By ~ 20

Author(s):

A. Howie

Keyword(s):

Electron Microscopy ◽

Secondary Electron Emission ◽

Threshold Energy ◽

Environmental Scanning Electron Microscopy ◽

Low Energy ◽

Environmental Scanning ◽

Scanned Probe Microscopy ◽

Low Energy Electrons ◽

Bandgap Semiconductors ◽

Threshold Energies

AbstractIn large bandgap semiconductors and insulators, the threshold energies for e–h pair production and ionization damage can lie above the vacuum level. For low energy imaging, a window is then opened whose width is potentially sensitive to local changes in work function, doping level, or acidity. Recent progress and future opportunities for damage-free imaging of these properties using low energy electrons are discussed in the light of the underlying physics, as well as of recent instrumental developments in low energy electron microscopy (LEEM), environmental scanning electron microscopy (ESEM), photoelectron emission microscopy (PEEM), scanned probe microscopy (SPM), and projection electron microscopy.

Download Full-text