Thermionic FEEM, PEEM and I/V Measurements of N-Doped CVD Diamond Surfaces

2000 ◽  
Vol 621 ◽  
Author(s):  
F.A.M. Köck ◽  
J.M. Garguilo ◽  
B. Brown ◽  
R.J. Nemanich
Keyword(s):  
Gas Phase ◽  
Field Emission ◽  
Electron Emission ◽  
Low Temperatures ◽  
Diamond Films ◽  
Cvd Diamond ◽  
Exponential Dependence ◽  
Diamond Surfaces ◽  
Cold Cathodes ◽  
Thermionic Field Emission

ABSTRACTImaging of field emission and photoemission from diamond surfaces is accomplished with a high resolution photo-electron emission microscope (PEEM). Measurements obtained as a function of sample temperature up to 1000°C display thermionic field emission images (TFEEM). The system can also record the emission current versus applied voltage. N-doped diamond films have been produced by MPCVD with a N/C gas phase ratio of 48. The surfaces display uniform emission in PEEM at all temperatures. No FEEM images are detectable below 500°C. At ∼680°C the T-FEEM and PEEM images are nearly identical in intensity and uniformity. This is to be contrasted with other carbon based cold cathodes in which the emission is observed from only a low density of highly emitting sites. The I/V measurements obtained from the N-doped films in the T-FEEM configuration show a component that depends linearly on voltage at low fields. At higher fields, an approximately exponential dependence is observed. At low temperatures employed (<700°C), the results indicate a thermionic component to the emitted current.

scholarly journals New Aspect on CVD Diamond Films. Electron Emission from Diamond Surfaces.

1999 ◽  
Vol 50 (6) ◽  
pp. 494-499
Author(s):  
Toshimichi ITO ◽  
Akimitsu HATTA ◽  
Akio HIRAKI
Keyword(s):  
Electron Emission ◽  
Diamond Films ◽  
Cvd Diamond ◽  
Diamond Surfaces

Investigation of Electron Emission From Si and Hot Filament CVD Diamond

1996 ◽  
Vol 424 ◽  
Author(s):  
J. Y. Shim ◽  
E. J. Chi ◽  
S. J. Rho ◽  
H. K. Baik
Keyword(s):  
Field Emission ◽  
Electron Emission ◽  
Cvd Diamond ◽  
Emission Characteristics ◽  
Turn On ◽  
Low Field ◽  
Hot Filament Cvd ◽  
Diamond Peak ◽  
Diamond Grain ◽  
Hot Filament

ABSTRACTThe field emission characteristics of the Si emitters and the diamond coated Si emitters are investigated. The Fowler-Nordheim plots of the two types of Si emitters show linear slopes. It means that the I-V characteristics follow the Fowler-Nordheim relation. Field emission for the two types of diamond coated Si emitters exhibits significant enhancement both in turn-on voltage and total emission current. The Raman spectrum shows that the high intensity graphite peak is observed with diamond peak and thereby large amounts of graphite may be included in the diamond grain boundary. It seems to be thought that the graphite participates in the low field emission. However, further investigations are needed to understand whether the graphite may enhance the emission characteristics of diamond or not.

Field Electron Emission from Carbon Nanotube Films on Diamond Films

2005 ◽  
Vol 475-479 ◽  
pp. 3587-3590
Author(s):  
K.J. Liao ◽  
W.L. Wang ◽  
Y.T. Wang ◽  
J.W. Lu ◽  
X.L. Sun
Keyword(s):  
Carbon Nanotubes ◽  
Carbon Nanotube ◽  
Field Emission ◽  
Electron Emission ◽  
Diamond Films ◽  
Chemical Vapour ◽  
Polycrystalline Diamond ◽  
Field Electron Emission ◽  
Field Electron ◽  
Nanotube Films

The field electron emission from carbon nanotube films on polycrystalline diamond films was investigated. The carbon nanotubes and diamond films on Si substrates were prepared by a conventional hot filament chemical vapour deposition. The films obtained were characterized by scanning electron microscopy and Raman spectroscopy. The field emission properties of the samples were measured in an ion-pumped vacuum chamber at a pressure of 10-6 Pa.. The experimental results showed that the field emission behaviours of carbon nanotubes/diomond films structure have greatly been improved as compared with carbon nanotubes and diamond films, respectively. A turn-on field of 1.0 V/µm and a maximum current of 500 µA at 1.5 V/µm were observed, which were lower than those of carbon nanotubes and polycrystalline diamond films, respectively. This improvement was attributed to the tip shape of sample surface, which provided an additional local increase in electric field at the tube ends.

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.

scholarly journals Relationship between Electron Emission from the Surface of CVD Diamond Films and Defects Density.

1995 ◽  
Vol 46 (7) ◽  
pp. 674-675
Author(s):  
Yukio AKIBA ◽  
Yoichi HIROSE ◽  
Tateki KUROSU ◽  
Masamori IIDA ◽  
Yoshiyuki SHOW ◽  
...  
Keyword(s):  
Electron Emission ◽  
Diamond Films ◽  
Cvd Diamond

scholarly journals Measurement of the secondary electron emission from CVD diamond films using phosphor screen detectors

2015 ◽  
Vol 10 (03) ◽  
pp. P03004-P03004 ◽  
Author(s):  
R. Vaz ◽  
P.W. May ◽  
N.A. Fox ◽  
C.J. Harwood ◽  
V. Chatterjee ◽  
...  
Keyword(s):  
Electron Emission ◽  
Secondary Electron ◽  
Secondary Electron Emission ◽  
Diamond Films ◽  
Cvd Diamond ◽  
Phosphor Screen
Sign in / Sign up

Export Citation Format

Share Document