Microstructural Evolution of Radiation-Induced Defects in Semi-Insulating SiC During Isochronal Annealing

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.

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Microstructural Evolution of Radiation Induced Defects In ZnO During Isochronal Annealing

MRS Proceedings ◽

10.1557/proc-540-207 ◽

1998 ◽

Vol 540 ◽

Cited By ~ 8

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.

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Effects of radiation-induced defects on microstructural evolution of Fe–Cr model alloys

Journal of Nuclear Materials ◽

10.1016/j.jnucmat.2008.12.079 ◽

2009 ◽

Vol 386-388 ◽

pp. 165-168 ◽

Cited By ~ 6

Author(s):

J. Kwon ◽

T. Toyama ◽

Y.-M. Kim ◽

W. Kim ◽

J.-H. Hong

Keyword(s):

Microstructural Evolution ◽

Radiation Induced ◽

Effects Of Radiation ◽

Induced Defects

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Xenon ion irradiation of superconducting YBa2Cu3O7 thin films

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100173595 ◽

1990 ◽

Vol 48 (4) ◽

pp. 92-93

Author(s):

H. Watanabe ◽

B. Kabius ◽

B. Roas ◽

K. Urban

Keyword(s):

Defect Formation ◽

Ion Irradiation ◽

High Resolution Electron Microscopy ◽

Structural Disorder ◽

Flux Lines ◽

Pinning Effect ◽

Magnetic Flux Lines ◽

Resolution Electron ◽

Radiation Induced ◽

Induced Defects

Recently it was reported that the critical current density(Jc) of YBa2Cu2O7, in the presence of magnetic field, is enhanced by ion irradiation. The enhancement is thought to be due to the pinning of the magnetic flux lines by radiation-induced defects or by structural disorder. The aim of the present study was to understand the fundamental mechanisms of the defect formation in association with the pinning effect in YBa2Cu3O7 by means of high-resolution electron microscopy(HRTEM).The YBa2Cu3O7 specimens were prepared by laser ablation in an insitu process. During deposition, a substrate temperature and oxygen atmosphere were kept at about 1073 K and 0.4 mbar, respectively. In this way high quality epitaxially films can be obtained with the caxis parallel to the <100 > SrTiO3 substrate normal. The specimens were irradiated at a temperature of 77 K with 173 MeV Xe ions up to a dose of 3.0 × 1016 m−2.

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