Highly efficient time-of-flight spectrometer for studying low-energy secondary emission from dielectrics: Secondary-electron emission from LiF film

2003 ◽  
Vol 74 (3) ◽  
pp. 1274-1277 ◽  
Author(s):  
S. N. Samarin ◽  
O. M. Artamonov ◽  
D. K. Waterhouse ◽  
J. Kirschner ◽  
A. Morozov ◽  
...  
1999 ◽  
Vol 558 ◽  
Author(s):  
J.E. Yater ◽  
A. Shih ◽  
D.S. Katzer

ABSTRACTSecondary electron emission spectroscopy is used to examine the transport and emission of low-energy electrons in several wide bandgap materials. In particular, the secondary emission properties of C(100), C(111), and CVD diamond samples are compared in order to examine the effect of crystallographic orientation on the emission characteristics. Very high yields are obtained from hydrogenated and cesiated negative-electron-affinity surfaces of all three samples, indicating that low-energy electrons are transported and emitted very efficiently in the diamond materials. While the energy distribution of the emitted electrons is found to be sharply peaked at low energy for all three samples, the energy distributions measured from the C(111) surfaces are broader and reveal structure in the energy gap. The different emission processes at the C(100) and C(111) surfaces may account for the energy distributions observed from the polycrystalline CVD diamond. Finally, initial secondary emission measurements are taken from GaN and AlGaN films grown by molecular beam epitaxy. The secondary emission is not as strong as from the diamond samples, and the measurements reveal the impact of interface and surface barriers on the emission process.


Author(s):  
R. D. Heidenreich

This program has been organized by the EMSA to commensurate the 50th anniversary of the experimental verification of the wave nature of the electron. Davisson and Germer in the U.S. and Thomson and Reid in Britian accomplished this at about the same time. Their findings were published in Nature in 1927 by mutual agreement since their independent efforts had led to the same conclusion at about the same time. In 1937 Davisson and Thomson shared the Nobel Prize in physics for demonstrating the wave nature of the electron deduced in 1924 by Louis de Broglie.The Davisson experiments (1921-1927) were concerned with the angular distribution of secondary electron emission from nickel surfaces produced by 150 volt primary electrons. The motivation was the effect of secondary emission on the characteristics of vacuum tubes but significant deviations from the results expected for a corpuscular electron led to a diffraction interpretation suggested by Elasser in 1925.


2005 ◽  
Vol 473-474 ◽  
pp. 293-296
Author(s):  
György Vida ◽  
Ildikó Beck ◽  
V. Katalin Josepovits ◽  
Miklós Győr

In the present paper the secondary emission and work function of W covered with different thickness Ba layers are compared. The secondary emission and work function were measured by Work Function Spectroscopy (WFS). It is clearly pointed out that the thin Ba coating causes the the enhancement of electron induced secondary electron emission. In high pressure discharge lamps high secondary emission and high thermionic current are required for reliable operating conditions, i.e., for reaching the nominal burning voltage and current etc. The results prove that the Ba spreading on the W surface from an alkali earth tungstate material is advantageous for lowering the work function and, simultaneously, for increasing the secondary emission yield.


2017 ◽  
Vol 13 ◽  
pp. 21-27 ◽  
Author(s):  
V. Kvon ◽  
E. Oyarzabal ◽  
E. Zoethout ◽  
A.B. Martin-Rojo ◽  
T.W. Morgan ◽  
...  

Sign in / Sign up

Export Citation Format

Share Document