Cathodoluminescence studies of threading dislocations in InGaN/GaN as a function of electron irradiation dose

2003 ◽  
Vol 93 (7) ◽  
pp. 3934-3939 ◽  
Author(s):  
S. J. Henley ◽  
D. Cherns
Keyword(s):  
Electron Irradiation ◽  
Irradiation Dose ◽  
Threading Dislocations ◽  
Electron Irradiation Dose

The Effect of Electron Irradiation Dose on the Profile of Electric Characteristics of GaAs VPE Layers

1993 ◽  
Vol 135 (1) ◽  
pp. K21-K24 ◽  
Author(s):  
C. D. Kourkoutas ◽  
B. Kovacs ◽  
P. C. Euthymiou ◽  
B. Szentpali ◽  
K. Somogyi ◽  
...  
Keyword(s):  
Electron Irradiation ◽  
Irradiation Dose ◽  
Electron Irradiation Dose

scholarly journals Formation of Silver Nanoparticles in PVA-PEG Hydrogel under Electron Irradiation

2019 ◽  
Vol 64 (1) ◽  
pp. 41
Author(s):  
V. B. Neimash ◽  
H. D. Kupianskyi ◽  
I. V. Olkhovyk ◽  
V. I. Styopkin ◽  
P. M. Lytvynchuk ◽  
...  
Keyword(s):  
Silver Nanoparticles ◽  
Electron Irradiation ◽  
Irradiation Dose ◽  
Chemical Reduction ◽  
Total Concentration ◽  
3D Microstructure ◽  
Order Of Magnitude ◽  
Radiation Induced ◽  
Electron Irradiation Dose ◽  
Scanning Electron

The formation of silver nanoparticles in a hydrogel on the basis of polyvinyl alcohol and polyethylene glycol at its crosslinking under the electron irradiation has been studied using the optical spectroscopy and scanning electron microscopy methods. The growth of nanoparticles 40–70 nm in size and their clustering into aggregates about a few hundred nanometers in diameter are demonstrated. The total concentration of nanoparticles and their size correlate with the concentration of ionic silver in the initial solution and the electron irradiation dose. The formation of nanoparticles is interpreted as a result of the radiation-induced chemical reduction of silver in the solution that is spatially confined in the cells of a 3D microstructure in the crosslinked hydrogel. The radiation-crosslinked hydrogel demonstrates an antiseptic effect for 7 of 8 tested microorganisms at silver concentrations of 0.001–0.003 wt.%, which is at least an order of magnitude lower than effective concentrations of ionic and colloidal silvers.

Effect of electron irradiation dose on the performance of avalanche photodiode electron detectors

2009 ◽  
Vol 105 (1) ◽  
pp. 014506 ◽  
Author(s):  
Taizo Kawauchi ◽  
Markus Wilde ◽  
Katsuyuki Fukutani ◽  
Tatsuo Okano ◽  
Shunji Kishimoto
Keyword(s):  
Electron Irradiation ◽  
Irradiation Dose ◽  
Avalanche Photodiode ◽  
Electron Irradiation Dose

Change of Micromechanical Properties of Polyethylene Induced by a Tribological Process in Polymer/Metal System

2006 ◽  
Vol 513 ◽  
pp. 75-84 ◽  
Author(s):  
J. Maszybrocka ◽  
Jerzy Cybo ◽  
J.E. Frąckowiak ◽  
K. Krzemień
Keyword(s):  
Plastic Deformation ◽  
Electron Irradiation ◽  
Friction Surface ◽  
Irradiation Dose ◽  
Spatial Arrangement ◽  
Metal System ◽  
Micromechanical Properties ◽  
Polymer Metal ◽  
Electron Irradiation Dose ◽  
Crystallinity Band

The influence of a tribological process in the polymer/metal system on changes in microhardness (H) and Young’s modulus (E) of the surface under friction and UHMWPE volume has been studied. Twelve samples of polyethylene characterized by a different degree of initial plastic deformation and different electron irradiation dose were analyzed. For four of the samples a decrease by 5÷10 times in polyethylene degradation has been found. This result is promising in that a prolonged durability can be expected in case of application for endoprostheses acetabular cups. It has been found also that a polyethylene material irradiated after initial prestraining only once shows enhanced micromechanical properties after friction. It has been found that this result was due to reorientation of lamellas on the friction surface taking place during deformation which accompanies the tribological process. It has been proved that the increase of H and E values in the layers situated at a depth of 1.5 mm÷7.5 mm is due to a decrease of the free volume centers in the UHMWPE polyethylene and to an increase of the degree of spatial arrangement of the structure (absorption in crystallinity band of FTIR spectrum).

Defects in Electron Irradiation Te-Doped GaSb Studied by Positron Lifetime Spectroscopy

2008 ◽  
Vol 607 ◽  
pp. 140-142
Author(s):  
H. Li ◽  
J.Y. Ke ◽  
J.B. Pang ◽  
Bo Wang ◽  
Z. Wang
Keyword(s):  
Electron Irradiation ◽  
Irradiation Dose ◽  
Room Temperature ◽  
Positron Lifetime ◽  
Rydberg States ◽  
Average Lifetime ◽  
Shallow Trap ◽  
Lifetime Measurements ◽  
Positron Lifetime Spectroscopy ◽  
Antisite Defects

Defects induced by electron irradiation in Te-doped liquid-encapsulated Czochralski–grown GaSb were studied by the positron lifetime spectroscopy. The lifetime measurements under room temperature indicated there were VGa-related defects with a characteristic lifetime of 298 ps in the heavily Te-doped as-grown GaSb samples. The average lifetime increased with the increase of irradiation dose in lightly Te-doped GaSb,but the behavior was opposite in the heavily Te-doped samples. It should be due to the shift of Fermi level in heavily Te-doped GaSb and the occurrence of gallium vacancies in different charge states. In the temperature dependence measurements carried out on heavily Te-doped samples, we observed positron shallow trap, and this shallow trap should be attributed to positrons forming hyrogenlike Rydberg states with GaSb antisite defects.

Degradation of Intersubband Transitions in Electron Irradiated GaAs/AlGaAs Multiple Quantum Wells With Superlattice Barriers

1999 ◽  
Vol 607 ◽  
Author(s):  
C.P. Morath ◽  
M.O. Manasreh ◽  
H.S. Gingrich ◽  
H.J. von Bardeleben ◽  
P. Ballet ◽  
...  
Keyword(s):  
Excited State ◽  
Quantum Wells ◽  
Electron Irradiation ◽  
Ground State ◽  
Irradiation Dose ◽  
Multiple Quantum Wells ◽  
Multiple Quantum ◽  
Intersubband Transitions ◽  
First Excited State ◽  
Induced Defects

AbstractIntersubband transitions in GaAs/AIGaAs multiple quantum wells (MQWs) are studied as a function of 2 MeV electron irradiation doses using the optical absorption technique. The MQW structure was designed with a 5 period Al.4Ga.6As/GaAs superlattice barrier, and two transitions are observed in the spectra. These transitions occur from the ground state to the first excited state and to the miniband formed by the superlattice barrier. The total integrated area from both transition spectra are studied as a function of temperature and electron irradiation dose. For the ground state to first excited state transition the total integrated area decreases exponentially as the irradiation dose increases, which could be explained in terms of the trapping of the 2D-electron gas in the quantum well by the irradiation induced defects. In comparison, the intensity of the ground state to miniband transition was found to increase exponentially as a function of the irradiation dose. Two possible explanations for this behavior are suggested. The temperature dependence of the integrated area of both transitions is also presented.

Sign in / Sign up

Export Citation Format

Share Document