Electron emission properties of laser pulsed GaAs negative electron affinity photocathodes

1990 ◽  
Vol 8 (6) ◽  
pp. 1853 ◽  
Author(s):  
Colin A. Sanford
Keyword(s):  
Electron Affinity ◽  
Electron Emission ◽  
Negative Electron Affinity ◽  
Emission Properties

Exciton-derived Electron Emission from (001) Diamondp–nJunction Diodes with Negative Electron Affinity

2008 ◽  
Vol 1 (1) ◽  
pp. 015004 ◽  
Author(s):  
Daisuke Takeuchi ◽  
Toshiharu Makino ◽  
Sung-Gi Ri ◽  
Norio Tokuda ◽  
Hiromitsu Kato ◽  
...  
Keyword(s):  
Electron Affinity ◽  
Electron Emission ◽  
Negative Electron Affinity

Characterization of Secondary Electron Emission from Materials with Low or Negative Electron Affinity

1998 ◽  
Vol 509 ◽  
Author(s):  
J.E. Yater ◽  
A. Shih
Keyword(s):  
Energy Distribution ◽  
Surface Properties ◽  
Electron Affinity ◽  
Electron Emission ◽  
Secondary Electron ◽  
Surface Composition ◽  
Secondary Electron Emission ◽  
Emission Characteristics ◽  
Negative Electron Affinity ◽  
Diamond Surfaces

AbstractSecondary electron emission spectroscopy is used to examine the emission characteristics of diamond films as a function of the bulk and surface properties. We find significant variation in the secondary electron yields measured from diamond surfaces even when energy distribution measurements indicate that a low or negative electron affinity is present. In particular, we observe that the material properties, such as bulk and surface uniformity, surface composition, and impurity and defect concentrations, have a strong affect on the secondary electron yield measurements. Furthermore, the energy distribution of the emitted electrons is found to vary with adsorbate species. In certain cases, the energy distribution changes with adsorbate coverage even though the measured electron intensity remains unchanged. From an analysis of the data, we identify bulk and surface properties needed to optimize the emission characteristics.

Effect of Annealing and Microwave Hydrogen Plasma Treatment on Structural, Chemical, and Electronic Properties of Ion Irradiated Diamond Films

2000 ◽  
Vol 650 ◽  
Author(s):  
Alexander Laikhtman ◽  
Alon Hoffman
Keyword(s):  
Plasma Treatment ◽  
Electron Affinity ◽  
Electron Emission ◽  
Hydrogen Plasma ◽  
Diamond Films ◽  
Ion Bombardment ◽  
Near Surface ◽  
Diamond Surfaces ◽  
X Ray ◽  
Emission Properties

ABSTRACTIn the present study we correlate between the secondary electron emission (SEE) of variously treated Xe+ ion-damaged diamond films and their bonding structure in the near-surface region as identified by near edge X-ray absorption fine structure (NEXAFS) spectroscopy and X-ray photoelectron spectroscopy. The 50 keV Xe+ ion bombardment of hydrogenated polycrystalline diamond films to a dose of 2×1015 cm−2 results in the transformation of near-surface diamond to sp2-bonded amorphous carbon, increased oxygen adsorption, shift of the electron affinity from negative to positive, and strong degradation of its electron emission properties, although it does not induce a pronounced depletion of hydrogen. Exposure of the ion-bombarded films to microwave (MW) hydrogen plasma treatment for 30 min produces negative electron affinity diamond surfaces, but only partially regenerates SEE properties, retains some imperfection in the near-surface atomic layers, as determined by NEXAFS, and the concentration of oxygen remains relatively high. Subsequent annealing to 610 °C produces oxygen-free diamond films and somewhat increases their SEE. Annealing to 1000 °C results in desorption of the surface hydrogen, formation of a positive electron affinity surfaces and drastically degrades their electron emission properties. Prolonged, up to three hours MW hydrogen plasma treatment of as-implanted diamond films gradually improves the crystal quality and results in further increase of SEE intensity. This treatment does not, however, substantially reduce the concentration of oxygen in the previously damaged diamond, indicating its bulk diffusion during or after ion bombardment. To fully recover electron emission properties it is necessary to both remove the defects and hydrogenate the diamond surfaces.

Investigation of electron emission site of p–i–n diode-type emitters with negative electron affinity

2014 ◽  
Vol 53 (5S1) ◽  
pp. 05FP07
Author(s):  
Daisuke Takeuchi ◽  
Satoshi Koizumi ◽  
Toshiharu Makino ◽  
Hiromitsu Kato ◽  
Hideyo Okushi ◽  
...  
Keyword(s):  
Electron Affinity ◽  
Electron Emission ◽  
Negative Electron Affinity

scholarly journals Electron emission from conduction band of diamond with negative electron affinity

2009 ◽  
Vol 80 (16) ◽  
Author(s):  
H. Yamaguchi ◽  
T. Masuzawa ◽  
S. Nozue ◽  
Y. Kudo ◽  
I. Saito ◽  
...  
Keyword(s):  
Conduction Band ◽  
Electron Affinity ◽  
Electron Emission ◽  
Negative Electron Affinity
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