Electron Field Emission from Self-Organized Micro-Emitters of sp3-Bonded 5H Boron Nitride with Very High Current Density at Low Electric Field

2004 ◽  
Vol 108 (17) ◽  
pp. 5182-5184 ◽  
Author(s):  
Shojiro Komatsu ◽  
Akio Okudo ◽  
Daisuke Kazami ◽  
Dmitri Golberg ◽  
Yubao Li ◽  
...  
Keyword(s):  
Boron Nitride ◽  
Electric Field ◽  
Field Emission ◽  
Current Density ◽  
High Current Density ◽  
Electron Field Emission ◽  
High Current ◽  
Self Organized ◽  
Electron Field ◽  
Very High

Electron Field Emission from Nano-Diamond Films

2001 ◽  
Vol 704 ◽  
Author(s):  
S.G. Wang ◽  
Q. Zhang ◽  
S.F. Yoon ◽  
J. Ahn ◽  
Q. Wang ◽  
...  
Keyword(s):  
Grain Size ◽  
Electric Field ◽  
Field Emission ◽  
Current Density ◽  
Diamond Films ◽  
Emission Current Density ◽  
Hydrogen Gas ◽  
Emission Current ◽  
Electron Field Emission ◽  
Electron Field

AbstractIn this paper, the field emission properties of nano-diamond films were investigated by measuring the curves of emission current density (J) versus applied electric field (E). The nano-diamond films were prepared on n-type (100) silicon substrate by microwave plasma enhanced chemical vapor deposition (MPECVD) technique using a gas mixture of nitrogen-methane-hydrogen. Field emission results show that, with increasing hydrogen gas flow ratio of [H2]/[N2+CH4+H2] from 0 to 10 %, diamond grain size increases from 5 to 60 nm, threshold electric field for electron field emission increases from 1.2 to 5.75 V/μm, and emission current density decreases from 820 to 560 μA/cm2, demonstrating that small grain size nano-diamond films are promising as a cathode material for low-field electron emitters.

NEEDLE CATHODES FOR HIGH-BRIGHTNESS BEAMS

2007 ◽  
Vol 22 (22) ◽  
pp. 3784-3793 ◽  
Author(s):  
C. H. BOULWARE ◽  
J. D. JARVIS ◽  
H. L. ANDREWS ◽  
C. A. BRAU
Keyword(s):  
Field Emission ◽  
Current Density ◽  
High Current Density ◽  
Thermionic Emission ◽  
High Current ◽  
High Brightness ◽  
Electron Sources ◽  
Schottky Effect ◽  
Surface Electric Field ◽  
Very High

At the tips of sharp needles, the surface electric field is enhanced by many orders of magnitude. This intensifies thermionic emission and photoemission of electrons through the Schottky effect, and reduces the effect of space charge. The increased current density improves the brightness of electron sources by orders of magnitude. In addition, at very high fields (>109 V/m ), field emission and photo-field emission produce very high current density. Arrays of needles can be used to achieve high total current.

Electron field emission from boron nitride nanofilm and its application to graphite nanofiber

2003 ◽  
Vol 21 (5) ◽  
pp. 2212 ◽  
Author(s):  
Chiharu Kimura ◽  
Tomohide Yamamoto ◽  
Shingo Funakawa ◽  
Masaaki Hirakawa ◽  
Hirohiko Murakami ◽  
...  
Keyword(s):  
Boron Nitride ◽  
Field Emission ◽  
Electron Field Emission ◽  
Electron Field

Optical and Electron Emission Properties of h-BN Films Codoped with Mg and O Atoms

2013 ◽  
Vol 566 ◽  
pp. 175-178
Author(s):  
Shinji Ohtani ◽  
Kenkichiro Kobayashi
Keyword(s):  
Electric Field ◽  
Field Emission ◽  
Electron Emission ◽  
Electron Field Emission ◽  
Emission Properties ◽  
Electron Field ◽  
Quartz Substrates ◽  
Lower Electric Field

Films of hexagonal BN (h-BN) codoped with Mg and O atoms were grown on n-type Si and quartz substrates heated at 500 °C by sputtering targets consisting of h-BN and MgO powders. An absorption is seen at a wavelength < 400 nm for h-BN films prepared in an Ar atmosphere. In contrast, films prepared from the target containing 0.25 mol% MgO in an atmosphere of Ar + 1% O2 shows an absorption at a wavelength < 260 nm and an electron field emission at a lower electric field of 3.6 V/μm.

Electrostatic and Electrodynamic Field Analyses of 33kV Line Insulators

2006 ◽  
Vol 7 (3) ◽  
Author(s):  
Ibrahim A. Metwally ◽  
Md Abdus Salam ◽  
Ali Al-Maqrashi ◽  
Saif AR Sumry ◽  
Saif SH Al-Harthy
Keyword(s):  
Electric Field ◽  
Current Density ◽  
High Current Density ◽  
Experimental Tests ◽  
Finite Element Models ◽  
High Current ◽  
Density Profiles ◽  
Fully Integrated ◽  
Software Modules ◽  
Simulation Results

Electrostatic and electrodynamic field analyses of 33kV line insulators were introduced to compare the electric-field and the current density profiles of commonly used line insulators in Oman; namely, silicone rubber (SiR) and porcelain line post insulators, and porcelain cap and pin insulator string. SLIM software package was used for such simulation, which is a fully integrated collection of software modules that provides facilities for the generation and solution of electromagnetic finite element models. The simulation results reveal that for the electrostatic simulation under pollution conditions, SiR and porcelain line-post insulators give maximum values of the electric field of 360kV/m and 1700kV/m, respectively. The latter value exceeds the recommended electric field level of 500kV/m. For the electrodynamic simulation under pollution conditions, the electric field and the current density are much higher for porcelain insulator compared to those of SiR insulator. The simulation of four cap-pin standard insulator string reveals that there is high electric field (1250kV/m) at the cap-insulator gap which can cause high current density for polluted case. Finally, the trend of the simulation results has been verified by experimental tests, which has been conducted on different 33kV line insulators having different designs and materials.

Electron field emission from ZnO self-organized nanostructures and doped ZnO:Ga nanostructured films

2009 ◽  
Vol 40 (2) ◽  
pp. 229-231 ◽  
Author(s):  
V.A. Karpyna ◽  
A.A. Evtukh ◽  
M.O. Semenenko ◽  
V.I. Lazorenko ◽  
G.V. Lashkarev ◽  
...  
Keyword(s):  
Field Emission ◽  
Electron Field Emission ◽  
Nanostructured Films ◽  
Self Organized ◽  
Electron Field
Sign in / Sign up

Export Citation Format

Share Document