Electron traps in n-GaAs irradiated with high electron beam fluxes at high temperatures

1988 ◽  
Vol 105 (1) ◽  
pp. K57-K60 ◽  
Author(s):  
V. N. Brudnyi ◽  
V. V. Peschev
1991 ◽  
Vol 13 (1-4) ◽  
pp. 165-172 ◽  
Author(s):  
M.G. Rosenfield ◽  
S.A. Rishton ◽  
D.P. Kern ◽  
D.E. Seeger ◽  
C.A. Whiting

2009 ◽  
Vol 156-158 ◽  
pp. 487-492 ◽  
Author(s):  
M.V. Zamoryanskaya

In this paper the new method for determination of luminescent centers concentration are discussed. While the possibility of electron traps determination and definition of its activation energy are suggested. The cathodoluminescent (CL) method was used. The determination of luminescent centers concentration in silicon oxide is based on the measurements of dependences of CL intensity on electron beam current. The presence and energy of activation of electron traps were studied by measurement of rise time and decay of luminescent band during the stationary irradiation of silica by electron beam.


2012 ◽  
Vol 2012 ◽  
pp. 1-10 ◽  
Author(s):  
Chao-Wei Lin ◽  
Hsien-Chin Chiu

This study examines the praseodymium-oxide- (Pr2O3-) passivated AlGaN/GaN metal-insulator-semiconductor high electron mobility transistors (MIS-HEMTs) with high dielectric constant in which the AlGaN Schottky layers are treated with P2S5/(NH4)2SX+ ultraviolet (UV) illumination. An electron-beam evaporated Pr2O3insulator is used instead of traditional plasma-assisted chemical vapor deposition (PECVD), in order to prevent plasma-induced damage to the AlGaN. In this work, the HEMTs are pretreated with P2S5/(NH4)2SXsolution and UV illumination before the gate insulator (Pr2O3) is deposited. Since stable sulfur that is bound to the Ga species can be obtained easily and surface oxygen atoms are reduced by the P2S5/(NH4)2SXpretreatment, the lowest leakage current is observed in MIS-HEMT. Additionally, a low flicker noise and a low surface roughness (0.38 nm) are also obtained using this novel process, which demonstrates its ability to reduce the surface states. Low gate leakage current Pr2O3and high-kAlGaN/GaN MIS-HEMTs, with P2S5/(NH4)2SX+ UV illumination treatment, are suited to low-noise applications, because of the electron-beam-evaporated insulator and the new chemical pretreatment.


2007 ◽  
Vol 22 (23) ◽  
pp. 4254-4264
Author(s):  
M. BOSCOLO ◽  
M. FERRARIO ◽  
V. FUSCO ◽  
M. MIGLIORATI ◽  
L. PALUMBO ◽  
...  

In the frame of the R&D activity foreseen for the first phase of the SPARX project, the SPARXINO test facility is meant to provide an ultra-high electron beam at 1.2-1.5 GeV, able to drive SASE and seeded FEL experiments in the 10-3 nm range. The proposed layout is analyzed regarding its sensitivity to laser pulse jitter effects and microbunching instability limitations. First simulation results are presented.


2018 ◽  
Vol 66 ◽  
pp. 151-165
Author(s):  
Morten Leth Hjuler ◽  
Vidar Folke Hansen ◽  
Ida Lykke Fabricius

Scanning and transmission electron microscopy (SEM and TEM) are capable of characterising the morphology and structure of sub-micron size substances attached to chalk particle surfaces. Some characteristics, however, may originate from sample preparation or reflect interaction between sample and the electron beam. Misinterpretation of surface features may lead to wrong conclusions regarding grain surface properties and cementation level and thus to erroneous characterisation of hydrocarbon reservoirs with respect to e.g. wettability, mechanical strength and maximum burial depth. In SEM, conductive coatings may mask surface details or generate artificial ornamentations, and carbon adhesive discs may cause the chalk surface to be covered with a thin carbon film. Electron beam acceleration voltage controls the degree of detail revealed by the electron beam, but in SEM a high electron beam acceleration voltage may provoke bending or curling of ultrathin particles. Recent organic filaments may be confused with clay flakes, and authigenic non-carbonate minerals may have formed in the pore fluid and settled during fluid removal. In TEM, the high acceleration voltage may cause beam damage to calcite and transform the outermost atomic layers into Ca oxide. Thin graphite membranes observed by TEM may be contamination from the carbon film supporting the sample, and overlapping chalk particles in samples formed by drying of a suspension may give the impression of being cemented together. In TEM residual adhesive from the ion-milling process can be confused with cementation features.


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