scholarly journals Field-emission from parabolic tips: Current distributions, the net current, and effective emission area

2018 ◽  
Vol 25 (4) ◽  
pp. 043105 ◽  
Author(s):  
Debabrata Biswas
2019 ◽  
Vol 89 (10) ◽  
pp. 1615
Author(s):  
Е.О. Попов ◽  
А.Г. Колосько ◽  
М.А. Чумак ◽  
С.В. Филиппов

A variety of types for formal determination of one of the main parameters of field emission systems - the emission area was investigated. Using hemisphere on a cylindrical post model built using the COMSOL Multiphysics software package the relationship between known types of emission area estimation was shown. The corresponding values of emission currents were calculated. It was shown that the formal emission area (the ratio of the total current to the current density at the top) provides only ~ 75% of the emission current value. The effect of the anomalous behavior of the effective emission area (intercept of the trend line of current-voltage characteristics) is obtained when the voltage level changes in standard Fowler-Nordheim coordinates. A method for an experimental estimate of the field emission area using the modified Fowler-Nordheim coordinates ln (I/U^(2-η/6)) vs 1/U is proposed. The method is applied to the analysis of field emission data of a multi-tip nanocomposite emitter with carbon nanotubes.


1999 ◽  
Vol 558 ◽  
Author(s):  
V.G. Litovchenko ◽  
A.A. Evtukh ◽  
N.I. Klyui ◽  
YU.M. Litvin ◽  
S.Yu. Kudzinovsky ◽  
...  

ABSTRACTElectron field emission and electrical conductivity of undoped and nitrogen doped DLC films have been investigated. The films were grown by the PE CVD method from CH4:H2 and CH4:H2:N2 gas mixtures, respectively. By varying nitrogen content in the gas mixture over the range 0 to 45%, corresponding concentrations of 0 to 8 % (atomic) could be achieved in the films. Three different gas pressures were used in the deposition chamber: 0.2, 0.6 and 0.8 Torr. Emission current measurements were performed at approximately 10−6 Torr using the diode method with emitter-anode spacing set at 20 gm. The current - voltage characteristics of the Si field electron emission arrays covered with DLC films show that threshold voltage (Vth) varies in a complex manner with nitrogen content. As a function of nitrogen content, Vth initially increases rapidly, then decreases and finally increases again for the highest concentration. Corresponding Fowler-Nordheim (F-N) plots follow F-N tunneling over a wide range. The F-N plots were used for determination of the work function, threshold voltage, field enhancement factor and effective emission area. For a qualitative explanation of experimental results, we treat the DLC film as a diamond-like (sp3 bonded) matrix with graphite-like inclusions.


2019 ◽  
Vol 64 (10) ◽  
pp. 1530-1540 ◽  
Author(s):  
E. O. Popov ◽  
A. G. Kolosko ◽  
M. A. Chumak ◽  
S. V. Filippov
Keyword(s):  

Author(s):  
M. Ravi ◽  
K. S. Bhat ◽  
Mamta Khaneja ◽  
P. K. Chaudhury ◽  
Harsh

2020 ◽  
Vol 13 (2) ◽  
pp. 101-111

Abstract: In field electron emission (FE) studies, it is important to check and analyze the quality and validity of results experimentally obtained from samples, using suitably plotted current-voltage [Im(Vm)] measurements. For the traditional plotting method, the Fowler-Nordheim (FN) plot, there exists a so-called "orthodoxy test" that can be applied to the FN plot, in order to check whether or not the FE device/system generating the results is "ideal". If it is not ideal, then emitter characterization parameters deduced from the FN plot are likely to be spurious. A new form of FE Im(Vm) data plot, the so-called "Murphy-Good (MG) plot", has recently been introduced (R.G. Forbes, Roy. Soc. Open Sci. 6 (2019) 190912). This aims to improve the precision with which characterization-parameter values (particularly values of formal emission area) can be extracted from FE Im(Vm) data. The present paper compares this new plotting form with the older FN and Millikan-Lauritsen (ML) forms and makes an independent assessment of the consistency with which slope (and hence scaled-field) estimates can be extracted from an MG plot. It is shown that, by using a revised formula for the extraction of scaled-field values, the existing orthodoxy test can be applied to Murphy-Good plots. The development is reported of a prototype web tool that can apply the orthodoxy test to all three forms of FE data plot (ML, MG and FN). Keywords: Field emission, Field electron emission, Murphy-Good plot, Fowler-Nordheim plot, Millikan-Lauritsen plot, Orthodoxy test.


Sign in / Sign up

Export Citation Format

Share Document