Vacancy-Type Defects in Electron and Proton Irradiated II- VI Compounds

1996 ◽  
Vol 439 ◽  
Author(s):  
S. Brunner ◽  
W. Puff ◽  
P. Mascher ◽  
A. G. Balogh ◽  
H. Baumann
Keyword(s):  
Positron Annihilation ◽  
Proton Irradiation ◽  
Basic Properties ◽  
Radiation Induced ◽  
Induced Defects ◽  
Mev Protons

AbstractIn this contribution, we present a study aimed at investigating the basic properties of radiation induced defects in ZnS and ZnO and the influence of the atmosphere on the annealing characteristics of the defects. Positron annihilation experiments (both lifetime and Dopplerbroadening measurements) were performed on both single- and polycrystalline samples, irradiated with 3 MeV protons or 1 MeV electrons. For ZnS it was found that both electron and proton irradiation caused significant changes in the positron annihilation characteristics. The annealing of proton irradiated ZnS in air leads to significant oxidation and eventual transformation into ZnO.

Vacancy-Type Defects in Electron and Proton Irradiated II- VI Compounds

1996 ◽  
Vol 438 ◽  
Author(s):  
S. Brunner ◽  
W. Puff ◽  
P. Mascher ◽  
A. G. Balogh ◽  
H. Baumann
Keyword(s):  
Positron Annihilation ◽  
Proton Irradiation ◽  
Basic Properties ◽  
Radiation Induced ◽  
Induced Defects ◽  
Mev Protons

AbstractIn this contribution, we present a study aimed at investigating the basic properties of radiation induced defects in ZnS and ZnO and the influence of the atmosphere on the annealing characteristics of the defects. Positron annihilation experiments (both lifetime and Dopplerbroadening measurements) were performed on both single- and polycrystalline samples, irradiated with 3 MeV protons or 1 MeV electrons. For ZnS it was found that both electron and proton irradiation caused significant changes in the positron annihilation characteristics. The annealing of proton irradiated ZnS in air leads to significant oxidation and eventual transformation into ZnO.

Studies of Defects in ZnO by Positron Annihilation

1995 ◽  
Vol 378 ◽  
Author(s):  
Werner Puff ◽  
Sebastian Brunner ◽  
Peter Mascher ◽  
Adam G. Balogh
Keyword(s):  
Positron Annihilation ◽  
Colour Change ◽  
Doppler Broadening ◽  
Positron Annihilation Lifetime ◽  
Dark Orange ◽  
Radiation Induced ◽  
Induced Defects ◽  
Annealing Experiments ◽  
Mev Protons ◽  
Yellowish White

AbstractIn order to investigate the basic properties of radiation-induced defects in ZnO crystals, positron annihilation lifetime and Doppler-broadening measurements were performed on crystals sinterd for 18 hours at 1200 °C and irradiated with 3 MeV protons at 223 K. The irradiation induced a colour change of the specimens from the original yellowish-white to dark orange or even brown. Isochronal annealing experiments showed three annealing stages, centred at about 150 °C, 500 – 550 °C, and 750 °C, respectively. These stages are related to the annealing of variously sized vacancy complexes.

Microstructural Evolution of Radiation Induced Defects In ZnO During Isochronal Annealing

1998 ◽  
Vol 540 ◽  
Author(s):  
S. Brunner ◽  
W. Puff ◽  
P. Mascher ◽  
A.G. Balogh
Keyword(s):  
Room Temperature ◽  
Proton Irradiation ◽  
Positron Lifetime ◽  
Thermal Evolution ◽  
Isochronal Annealing ◽  
Doppler Broadening ◽  
Thermal Dependence ◽  
Radiation Induced ◽  
Induced Defects ◽  
Mev Protons

AbstractIn this study we discuss the microstructural changes after electron and proton irradiation and the thermal evolution of the radiation induced defects during isochronal annealing. The nominally undoped samples were irradiated either with 3 MeV protons to a fluence of 1.2× 1018 p/cm2 or with 1 MeV electrons to a fluence of 1×1018 e/cm2. The investigation was performed with positron lifetime and Doppler-broadening measurements. The measurements were done at room temperature and in some cases down to 10 K to investigate the thermal dependence of the trapping characteristics of the positrons.

Vacancy-Type Defects in Electron and Proton Irradiated II-VI Compounds

1998 ◽  
Vol 510 ◽  
Author(s):  
S. Brunner ◽  
W. Puff ◽  
P. Mascher ◽  
A.G. Balogh
Keyword(s):  
Band Gap ◽  
Proton Irradiation ◽  
Positron Lifetime ◽  
Wide Band ◽  
Compound Semiconductors ◽  
Doppler Broadening ◽  
Wide Band Gap ◽  
Radiation Induced ◽  
Induced Defects ◽  
Mev Protons

AbstractIn this contribution we present a study aimed at comparing results of positron-lifetime and Doppler-broadening measurements on the wide-band-gap compound semiconductors ZnS, ZnSe, and ZnTe. To investigate the basic properties of intrinsic and radiation induced defects the samples were irradiated either with 3 MeV protons or 1 MeV electrons. The isochronal annealing was performed in an Ar atmosphere. It was found that electron and proton irradiation cause different changes in the positron annihilation characteristics. Several annealing stages were observed, related to the annealing of variously sized vacancy complexes.

Annealing of radiation-induced defects in tungsten: Positron annihilation spectroscopy study

2019 ◽  
Vol 517 ◽  
pp. 148-151 ◽  
Author(s):  
O.V. Ogorodnikova ◽  
L. Yu Dubov ◽  
S.V. Stepanov ◽  
D. Terentyev ◽  
Yu.V. Funtikov ◽  
...  
Keyword(s):  
Positron Annihilation ◽  
Positron Annihilation Spectroscopy ◽  
Spectroscopy Study ◽  
Radiation Induced ◽  
Induced Defects

Defect Network in Superconducting Ceramic Oxides Studied by Neutron and Proton Irradiation

1990 ◽  
Vol 209 ◽  
Author(s):  
E. Mezzetti ◽  
D. Andreone ◽  
G. Castagno ◽  
R. Cherubini ◽  
S. Colombo ◽  
...  
Keyword(s):  
Critical Current Density ◽  
Proton Irradiation ◽  
Short Circuit ◽  
Oxide Ceramics ◽  
High Fluence ◽  
Ceramic Oxides ◽  
Radiation Induced ◽  
Proton Implantation ◽  
Induced Defects ◽  
Superconducting Ceramic

ABSTRACTThis paper investigates both transport properties and nature of superconductivity breakdown or, conversely, enhancement in oxide ceramics, due to radiation-induced defects.Low-fluence neutrons (≈107 n cm-2 at 3 MeV) can sensitively damage the samples, giving experimental evidence that the breakdown of coherent percolating paths produces decoupled domains. A set of preliminary measurements shows that high-fluence proton implantation can either damage or enhance critical current density in a currently non controllable way. In both cases strongly damaged or enhanced superconducting paths short-circuit the unaffected bulk network.

Effect of Proton Irradiation Induced Defects on 4H-SiC Schottky Diode X-Ray Detectors

2011 ◽  
Vol 679-680 ◽  
pp. 547-550
Author(s):  
Rupert C. Stevens ◽  
Konstantin Vassilevski ◽  
John E. Lees ◽  
Nicolas G. Wright ◽  
Alton B. Horsfall
Keyword(s):  
Schottky Diode ◽  
Nuclear Power ◽  
Proton Irradiation ◽  
Deep Level ◽  
High Dose ◽  
X Ray ◽  
Power Stations ◽  
Radiation Induced ◽  
Transient Spectroscopy ◽  
Induced Defects

Detectors capable of withstanding high radiation environments for prolonged periods of exposure are essential for the monitoring of nuclear power stations and nuclear waste as well as for space exploration. Schottky diode X-ray detectors were exposed to high dose proton irradiation (1013 cm-2, 50 MeV) and changes in the detection resolution (spectroscopic full width half-maximum) have been observed. Using Deep Level Transient Spectroscopy (DLTS) and the degradation of the electrical characteristics of the diode, we have shown that radiation induced traps located in the upper half of the bandgap have reduced the concentration of carriers.

Proton Irradiation Induced Defects in 611- and 4H-SiC

1998 ◽  
Vol 540 ◽  
Author(s):  
Werner Puff ◽  
Adam G. Balogh ◽  
Peter Mascher
Keyword(s):  
Proton Irradiation ◽  
Positron Lifetime ◽  
Doppler Broadening ◽  
Defect Complexes ◽  
Radiation Induced ◽  
Positron Lifetime Spectroscopy ◽  
Induced Defects ◽  
Irradiation Induced Defects ◽  
Type Sample

AbstractAnnealing of defects in proton irradiated bulk n-type 6H- and semi-insulating 4H-SiC has been investigated by positron lifetime spectroscopy and Doppler-broadening measurements. For the n-type sample radiation induced defects in dependence of the proton fluence were studied. Three or four annealing stages were found, during which the formation of larger defect complexes could be observed.

Radiation-Induced Defects in Electron and Proton Irradiated ZnS

1998 ◽  
Vol 540 ◽  
Author(s):  
S. Brunner ◽  
W. Puff ◽  
P. Mascher ◽  
A.G. Balogh
Keyword(s):  
Vapour Deposition ◽  
Proton Irradiation ◽  
Positron Lifetime ◽  
Chemical Vapour ◽  
Isochronal Annealing ◽  
Doppler Broadening ◽  
Defect Complexes ◽  
Radiation Induced ◽  
The Stability ◽  
Induced Defects

AbstractIn this contribution, we present a study aimed at investigating the microstructural changes of ZnS single crystals and CVD (chemical vapour deposition) grown crystals after electron and proton irradiation. Positron lifetime and Doppler-broadening measurements were performed to investigate the stability of the radiation induced defects and possible clustering mechanisms during isochronal annealing. After electron as well as proton irradiation the significant changes in the annihilation characteristics are indications of radiation induced open-volume-type defects. It is found that electron and proton irradiation causes different changes in the positron annihilation characteristics. After electron irradiation a significant defect component is observed which can be attributed to the annihilation in monovacancies. During isochronal annealing agglomerations to divacancy-type defects take place. Proton irradiation reveals a significantly different defect structure. Isochronal annealing causes agglomerations to larger defect complexes. The observed annealing stages are indications of the annealing of variously sized vacancy complexes.

High energy oxygen irradiation-induced defects in Fe-doped semi-insulating indium phosphide by positron annihilation technique

2017 ◽  
Vol 31 (04) ◽  
pp. 1750019
Author(s):  
S. Pan ◽  
A. Mandal ◽  
Md. A. Sohel ◽  
A. K. Saha ◽  
D. Das ◽  
...  
Keyword(s):  
Indium Phosphide ◽  
Positron Annihilation ◽  
Room Temperature ◽  
High Energy ◽  
Average Lifetime ◽  
Defect States ◽  
Positron Trapping ◽  
Radiation Induced ◽  
Induced Defects ◽  
Irradiation Induced Defects

Positron annihilation technique is applied to study the recovery of radiation-induced defects in 140 MeV oxygen (O[Formula: see text]) irradiated Fe-doped semi-insulating indium phosphide during annealing over a temperature region of 25[Formula: see text]C–650[Formula: see text]C. Lifetime spectra of the irradiated sample are fitted with three lifetime components. Trapping model analysis is used to characterize defect states corresponding to the de-convoluted lifetime values. After irradiation, the observed average lifetime of positron [Formula: see text] ps at room temperature is higher than the bulk lifetime by 21 ps which reveals the presence of radiation-induced defects in the material. A decrease in [Formula: see text] occurs during room temperature 25[Formula: see text]C to 200[Formula: see text]C indicating the dissociation of higher order defects, might be due to positron trapping in acceptor-type of defects ([Formula: see text]). A reverse annealing stage is found at temperature range of 250[Formula: see text]C–425[Formula: see text]C for [Formula: see text]-parameter probably due to the migration of vacancies and the formation of vacancy clusters. Increase in [Formula: see text]-parameter from 325[Formula: see text]C to 425[Formula: see text]C indicates the change in the nature of predominant positron trapping sites. Beyond 425[Formula: see text]C, [Formula: see text], [Formula: see text]-parameter and [Formula: see text]-parameter starts decreasing and around 650[Formula: see text]C, [Formula: see text] and [Formula: see text]-parameter approached almost the bulk value showing the annealing out of radiation-induced defects.

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