Distribution of radiation induced defects and modification of optical constants of GaAs implanted with high energy 56Fe ions

The isothermal annealing of n-Ge single crystals irradiated with 10-MeV electrons to the fluence Φ = 5 × 1015 cm−2 has been studied. On the basis of the measured temperature dependences of the Hall constant and by solving the electroneutrality equations, the concentrations of radiation-induced defects (A-centers) in irradiated n-Ge single crystals are calculated both before and after the annealing. An anomalous increase of the Hall constant is found, when the irradiated n-Ge single crystals were annealed at Tan = 403 K for up to 3 h. The annealing at the temperature Tan = 393 K for 1 h gave rise to the np conversion in the researched crystals. The revealed effects can be explained by the concentration growth of A-centers owing to the generation of vacancies at the annealing of disordered crystal regions.

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Capacitance Spectroscopy Study of High Energy Electron Irradiated and Annealed 4H-SiC

Materials Science Forum ◽

10.4028/www.scientific.net/msf.483-485.365 ◽

2005 ◽

Vol 483-485 ◽

pp. 365-368 ◽

Cited By ~ 3

Author(s):

Giovanni Alfieri ◽

Edouard V. Monakhov ◽

Margareta K. Linnarsson ◽

Bengt Gunnar Svensson

Keyword(s):

Deep Level ◽

Chemical Vapor ◽

High Energy ◽

Conduction Band Edge ◽

Energy Band Gap ◽

Annealing Step ◽

Radiation Induced ◽

Transient Spectroscopy ◽

Induced Defects ◽

Thermal Stability Of

Deep level transient spectroscopy (DLTS) was employed to investigate the annealing behaviour and thermal stability of radiation induced defects in nitrogen doped 4H-SiC epitaxial layers, grown by chemical vapor deposition (CVD). The epilayers have been irradiated with 15 MeV electrons and an isochronal annealing series has been carried out. The measurements have been performed after each annealing step and six electron traps located in the energy band gap range of 0.42-1.6 eV below the conduction band edge (Ec) have been detected.

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Electrophysical and Optical Properties of 4H-SiC Irradiated with Xe Ions

Materials Science Forum ◽

10.4028/www.scientific.net/msf.740-742.625 ◽

2013 ◽

Vol 740-742 ◽

pp. 625-628

Author(s):

N. Chuchvaga ◽

E. Bogdanova ◽

A. Strelchuk ◽

Evgenia V. Kalinina ◽

D.B. Shustov ◽

...

Keyword(s):

High Energy ◽

Partial Recovery ◽

Electrical Characteristics ◽

Stopping Distance ◽

Wide Range ◽

Order Of Magnitude ◽

Radiation Induced ◽

Temperature Radiation ◽

Induced Defects ◽

Partial Annealing

A comparative research of the cathodoluminescence and electrical characteristics of the samples 4H-SiC irradiated with high energy Xe ions (167 MeV) in wide range fluencies 4x109 –1x1011 cm-2 at temperatures 250C and 5000C are presented. After irradiation these samples were thermal annealed at 5000C for 30 min. Far-action effect at a depth of more than one order of magnitude of stopping distance was observed under Xe ions irradiation in 4H-SiC. An increase of the ion Xe fluencies increased the concentration of radiation-induced defects that resulted in rise of the compensation effect of conductivity in samples. Irradiation of 4H-SiC by Xe ions at 5000C was accompanied with "dynamic annealing" some low-temperature radiation-induced defects, which led to a partial recovery of the electrical characteristics of devices. The thermal annealing of irradiated samples led to additional partial annealing of radiation defects, which increases the radiation resource of devices based on 4H-SiC.

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Radiation-induced defects in thin Cu(In,Ga)Se2 films on exposure to high-energy electron irradiation

Journal of Applied Spectroscopy ◽

10.1007/s10812-006-0020-5 ◽

2005 ◽

Vol 72 (6) ◽

pp. 883-886 ◽

Cited By ~ 2

Author(s):

A. V. Mudryi ◽

V. F. Gremenok ◽

A. V. Ivanyukovich ◽

M. V. Yakushev ◽

Ya. V. Feofanov

Keyword(s):

Electron Irradiation ◽

High Energy ◽

Energy Electron ◽

High Energy Electron ◽

Radiation Induced ◽

Induced Defects

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

International Journal of Modern Physics B ◽

10.1142/s0217979217500199 ◽

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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Radiation-Induced Defects in Si after High Dose Proton Irradiation

Defect and Diffusion Forum ◽

10.4028/www.scientific.net/ddf.373.209 ◽

2017 ◽

Vol 373 ◽

pp. 209-212 ◽

Cited By ~ 2

Author(s):

Yurii V. Funtikov ◽

Leonid Yu. Dubov ◽

Yurii V. Shtotsky ◽

Sergey V. Stepanov

Keyword(s):

Bragg Peak ◽

Proton Irradiation ◽

Defect Formation ◽

High Energy ◽

High Dose ◽

Number Density ◽

High Energy Proton ◽

Energy Proton ◽

Radiation Induced ◽

Induced Defects

Experiments on investigation of the radiation defects produced as a result of high energy proton irradiation of single crystal Si wafers are carried out. Parameters of the proton irradiation facility are presented. It is shown that the most efficient radiation defect formation correlates with the position of the Bragg peak of ionization losses. LT spectra were measured just after irradiation and then after keeping Si samples during 3 months of at room T. We did not observe any variation of the number density of the defects, except for the 7th wafer, where most part of protons was stopped. An efficient annealing of the vacancy-type defects starts at temperatures slightly lower than 100 °C (during 10 min). Annealing at about 700 °C leads to recovering of the monoexponrntial shape of the LT spectra.

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Radiation-Resistant Properties of Inp-Related Materials

MRS Proceedings ◽

10.1557/proc-373-535 ◽

1994 ◽

Vol 373 ◽

Author(s):

Masafumi Yamaguchi ◽

Koshi Ando ◽

Hidehiko Kamada

Keyword(s):

Gamma Rays ◽

Minority Carrier ◽

Deep Level ◽

High Energy ◽

Carrier Injection ◽

High Energy Electrons ◽

Radiation Resistant ◽

Radiation Induced ◽

Transient Spectroscopy ◽

Induced Defects

AbstractIrradiation effects of high-energy electrons and protons, and 60Co gamma-rays on InP-related materials have been examined in comparison with those of GaAs and Si. Superior radiation-resistance of InP-related materials and their devices compared to GaAs and Si has been found by using deep-level transient spectroscopy (DLTS), photoluminescence (PL) and properties of devices such as solar cells and lightemitting devices. Moreover, minority-carrier injection enhanced annealing phenomena of radiation-induced defects in InP-related materials have also been observed even at low temperature of around 150K.

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High-Energy Electron and Proton Irradiation of Cu(In,Ga)Se2 Heterojunction Solar Cells

MRS Proceedings ◽

10.1557/proc-668-h3.2 ◽

2001 ◽

Vol 668 ◽

Cited By ~ 5

Author(s):

A. Jasenek ◽

A. Boden ◽

K. Weinert ◽

M. R. Balboul ◽

H. W. Schock ◽

...

Keyword(s):

Solar Cells ◽

Proton Irradiation ◽

High Efficiency ◽

High Energy ◽

Open Circuit ◽

Solar Cell Efficiency ◽

Heterojunction Solar Cells ◽

Cell Efficiency ◽

Radiation Induced ◽

Induced Defects

ABSTRACTWe investigate radiation-induced defects in high-efficiency Cu(In,Ga)Se2/CdS/ZnO heterojunction solar cells after 1-MeV electron and 4-MeV proton irradiation. We use electron and proton fluences of more than 1018 cm−2 and up to 1014 cm−2, respectively. The irradiation experiments performed at three independent electron irradiation facilities consistently prove the superior radiation resistance of these Cu(In,Ga)Se2 devices compared to other types of solar cells. The reduction of the solar cell efficiency in all experiments is predominantly caused by a loss ΔVOC of the open circuit voltage VOC. An analytical model describes ΔVOC in terms of radiation-induced defects enhancing recombination in the Cu(In,Ga)Se2 absorber material. From our model we extract the defect introduction rates for recombination centers in Cu(In,Ga)Se2 for the respective particles and energies. Isochronal annealing steps fully recover VOC of the irradiated Cu(In,Ga)Se2 solar cells. Exposure to temperatures of approx. 400 K are sufficient to restore the initial VOC within less than 5 %, even after excessive irradiation. The annealing process displays an activation energy of EA = 1.1 eV. Admittance spectroscopy directly reveals the generation and the annealing of radiation-induced defects.

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