Field Emission Energy Distribution and Current-Voltage Characteristics Using Single Tip Gated Diodes

1999 ◽  
Vol 558 ◽  
Author(s):  
John M Bernhard ◽  
Ambrosio A. Rouse ◽  
Edward D. Sosa ◽  
Bruce E. Gnade ◽  
David E. Golden ◽  
...  

ABSTRACTField emission current-voltage characteristics and simultaneous field emission electron energy distributions have been measured using single tip gate diodes. An energy distribution is generated at each step of a current-voltage characteristic using a compact low-cost simulated hemispherical energy analyzer. A PC programmed with graphics-based data acquisition software is used for data acquisition and control. The PC is connected to a CAMAC crate and a picoammeter through a GPIB interface. The picoammeter measures the current leaving the tip and the field emission electrons are energy analyzed, detected and processed in the CAMAC crate. The CAMAC crate also sends control voltages. to the gate anode and the energy analyzer. This apparatus was used to measure tip work functions and Fowler-Nordheim tip shape parameters for Mo and IrO2 field emission tips. Work function measurements from field emission tips are compared to photoelectric work function measurements from flat surfaces.

2019 ◽  
Vol 125 (5) ◽  
pp. 054502 ◽  
Author(s):  
Jonathan L. Shaw ◽  
John B. Boos ◽  
Byoung Don Kong ◽  
Jeremy T. Robinson ◽  
Glenn G. Jernigan

2013 ◽  
Vol 740-742 ◽  
pp. 1010-1013 ◽  
Author(s):  
Alexey V. Afanasyev ◽  
Boris V. Ivanov ◽  
Vladimir A. Ilyin ◽  
Alexey F. Kardo-Sysoev ◽  
Maria A. Kuznetsova ◽  
...  

This paper presents the results of research and development of two types diode structures based on wide bandgap 4H-SiC: drift step recovery diodes (DSRDs) and field emission diodes (FED). Diodes’ structure and manufacturing methods are reviewed. Diode’s characteristics were obtained (static current-voltage characteristics and capacitor-voltage characteristic, switching properties’ characteristics for DSRDs). Field emission 4H-SiC structures illustrated high (≥102 А/сm2) current densities at electric field intensity of approximately 10V/um. 4H-SiC DSRDs in the generator structure with a single oscillating contour allowed to form sub nanosecond impulses at a load 50 Ohm and 1,5-2kV amplitude for a single diode (current density at V=2kV J= 4•103 А/сm2),what is significantly higher than similar DSRD’s parameters obtained for silicon.


Author(s):  
Е.О. Попов ◽  
А.Г. Колосько ◽  
С.В. Филиппов

A method for testing the compliance of experimental current-voltage characteristics with a cold field emission mode is described. The method is based on the variation of voltage power-law exponent in the semilogarithmic coordinates ln (I/U^k) vs1/U, as well as the statistical analysis of experimental data fluctuations. It is shown that the current-voltage characteristics obtained using the high-voltage fast-scanning technique have a better fit to the field emission law than the characteristics given by a slow scanning with a constant voltage. A multi-tip nanocomposite emitter based on carbon nanotubes was taken as a sample. For processing experimental data, it was proposed to use modified Fowler-Nordheim coordinates with a voltage power-law exponent of 1.24.


Author(s):  
S.A. Bagdasaryan ◽  
S.A. Nalimov

To create field emission cathodes (autocathodes) used in the manufacture of displays and other devices, carbon nanowalls (CNW) are promising. The CNW layers are a porous material consisting of curved plates formed by graphene layers. The industrial use of CNW autocathodes is impeded by the heterogeneity and instability of the magnitude and density of the cathode current. To improve the characteristics of autocathodes, an AlN film is formed on the surface of the emitting substance, which also has the property of field emission. CNW was obtained from a gas mixture of H2 and CH4 activated by a dc glow discharge. The CNW layers were deposited on silicon substrates and substrates representing a layered structure made by forming an opal matrix (OM) layer on a Si substrate. AlN films with controlled composition and structure were prepared by RF magnetron reactive sputtering. CNW layers with a thickness of > 4 μm were obtained by successive growth of two CNW layers (Si/CNW/CNW structure). An additional CNW layer was also grown on the surface of the first layer coated with Ni (Si/CNW/Ni/CNW structure). AlN films were grown on a CNW layer (Si/CNW/AlN and Si/OM/Ni/CNW/AlN structures). It is shown that CNW plates are formed from graphene layers partially connected by atomic bonds (up to 30 layers) packed in a hexagonal lattice, and AlN films consisted of amorphous and axially textured crystalline phases. The current-voltage characteristics of the autocathodes were measured in a pulsed mode at a pressure of ~10−3 Pa. The Si/CNW/CNW structures are characterized by a threshold of autoemission of ≤ 3.6 V/μm and a high density of centers of emission. The current-voltage characteristics of the layered structures Si/CNW/AlN, Si/OM/Ni/CNW and Si/OM/Ni/CNW /AlN showed better emission properties compared to the Si/CNW structure. The current-voltage characteristics considered make it possible to predict the structure and composition of the emitting layer to improve the operational characteristics of multilayer autocathodes.


1996 ◽  
Vol 67 (6) ◽  
pp. 2207-2214 ◽  
Author(s):  
T. Saito ◽  
Y. Kiwamoto ◽  
Y. Tatematsu ◽  
Y. Yoshimura ◽  
M. Sakakibara ◽  
...  

2009 ◽  
Vol 615-617 ◽  
pp. 431-434 ◽  
Author(s):  
Pavel A. Ivanov ◽  
Alexander S. Potapov ◽  
Tat'yana P. Samsonova

Forward current-voltage characteristics of non-ideal Ti / 4H-SiC Schottky barriers with ideality factor n = 1.1 - 1.2 have been analyzed. The non-ideality is considered as a result of formation of a thin intermediate dielectric layer between the deposited titanium layer and 4H-SiC. Using experimental current-voltage characteristics, the electro-physical characteristics of Ti contacts such as the energy barrier height, the thickness of the intermediate layer and the energy distribution of the interface trap density are determined.


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