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

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.

Elevated Temperature Implantation of GaAs with Si Ions.

1996 ◽  
Vol 438 ◽  
Author(s):  
R. A. Brown ◽  
J. S. Williams
Keyword(s):  
Elevated Temperatures ◽  
Amorphous Layer ◽  
Ion Flux ◽  
Implantation Temperature ◽  
Transmission Electron ◽  
Order Of Magnitude ◽  
Residual Damage ◽  
Radiation Induced ◽  
Small Clusters ◽  
Induced Defects

AbstractThe formation of amorphous layers in GaAs during ion bombardment at elevated temperatures, where dynamic annealing of radiation-induced defects is substantial, is shown to be extremely sensitive to the ion flux, fluence, and implantation temperature. For example, with increasing fluence, damage can first build up extremely slowly, then suddenly collapse to the amorphous phase. Alternatively, for a constant ion fluence, a change in flux by one order of magnitude can change the critical temperature for amorphisation by 27°C, and at constant flux and fluence, a change of only 6°C can alter the residual damage from small clusters barely visible by conventional transmission electron microscopy and Rutherford backscattering to a thick amorphous layer. The temperature at which this occurs is strongly dependent upon the ion flux and fluence.

scholarly journals Features of Radiation-Defect Annealing in n-Ge Single Crystals Irradiated with High-Energy Electrons

2019 ◽  
Vol 64 (2) ◽  
pp. 151
Author(s):  
S. V. Luniov ◽  
A. I. Zimych ◽  
M. V. Khvyshchun ◽  
V. T. Maslyuk ◽  
I. G. Megela
Keyword(s):  
Single Crystals ◽  
High Energy ◽  
Measured Temperature ◽  
Hall Constant ◽  
Defect Annealing ◽  
Before And After ◽  
Temperature Dependences ◽  
Radiation Induced ◽  
Disordered Crystal ◽  
Induced Defects

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.

scholarly journals Wave and Tidal Controls on Embayment Circulation and Headland Bypassing for an Exposed, Macrotidal Site

2018 ◽  
Vol 6 (3) ◽  
pp. 94 ◽  
Author(s):  
R. McCarroll ◽  
Gerd Masselink ◽  
Nieves Valiente ◽  
Tim Scott ◽  
Erin King ◽  
...  
Keyword(s):  
Extreme Events ◽  
High Energy ◽  
Water Levels ◽  
Energy Conditions ◽  
Coastal Change ◽  
Extreme Waves ◽  
Starting Point ◽  
Wide Range ◽  
Order Of Magnitude ◽  
A Site

Headland bypassing is the transport of sediment around rocky headlands by wave and tidal action, associated with high-energy conditions and embayment circulation (e.g., mega-rips). Bypassing may be a key component in the sediment budget of many coastal cells, the quantification of which is required to predict the coastal response to extreme events and future coastal change. Waves, currents, and water levels were measured off the headland of a sandy, exposed, and macrotidal beach in 18-m and 26-m depths for 2 months. The observations were used to validate a Delft3D morphodynamic model, which was subsequently run for a wide range of scenarios. Three modes of bypassing were determined: (i) tidally-dominated control during low–moderate wave conditions [flux O (0–102 m3 day−1)]; (ii) combined tidal- and embayment circulation controls during moderate–high waves [O (103 m3 day−1)]; and (iii) multi-embayment circulation control during extreme waves [O (104 m3 day−1)]. A site-specific bypass parameter is introduced, which accurately (R2 = 0.95) matches the modelled bypass rates. A 5-year hindcast predicts bypassing is an order of magnitude less than observed cross-shore fluxes during extreme events, suggesting that bypassing at this site is insignificant at annual timescales. This work serves a starting point to generalise the prediction of headland bypassing.

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

2005 ◽  
Vol 483-485 ◽  
pp. 365-368 ◽  
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.

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

2005 ◽  
Vol 72 (6) ◽  
pp. 883-886 ◽  
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

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.

Radiation-Induced Defects in Si after High Dose Proton Irradiation

2017 ◽  
Vol 373 ◽  
pp. 209-212 ◽  
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.

Radiation-Resistant Properties of Inp-Related Materials

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.

Radiation-induced Defects in Nonradioactive Natural Minerals: Mineralogical and Environmental Significance

2003 ◽  
Vol 792 ◽  
Author(s):  
Georges Calas ◽  
Thierry Allard ◽  
Etienne Balan ◽  
Guillaume Morin ◽  
Stéphanie Sorieul
Keyword(s):  
Clay Minerals ◽  
Defect Formation ◽  
High Specific Surface Area ◽  
Radiation Background ◽  
Geochemical Parameters ◽  
Wide Range ◽  
Natural Analogues ◽  
Radiation Induced ◽  
Electronic Defects ◽  
Induced Defects

ABSTRACTNatural short-lived radionuclides generate electronic defects in minerals, such as trapped electrons and positive holes, often associated with element impurities, which act as final traps over geological periods. Two main examples will be illustrated. The first example will concern the point defects, which are observed in clay minerals. The high specific surface area makes clay minerals sensitive to the geochemical radiation background and provides a record of the past occurrence of radionuclides in geological systems. In kaolinite, three types of hole-centers are trapped by oxygen atoms linked to Si- or Al-sites. An experimental dosimetry gives the paleodose, which can be used either to assess mean past U-concentration or for kaolinite dating, depending on the available geochemical parameters. The detection of past migrations of radioelements in natural analogues may be used in the safety assessment of radioactive waste disposals. The second example will concern the role of mineral impurities in defect formation and stabilization. Natural fluorites (CaF2) exhibit hole-and electron-centers trapped on several rare earths and oxygen impurities, often present at the ppm level, which are responsible for the wide range of coloration observed in natural fluorites. Ca colloids may form under severe irradiation and give rise to a characteristic absorption. The thermal stability of radiation-induced defects gives constraints on the evolution of fluorites as a function of temperature and time. Other minerals, such as apatite, confirm the importance of impurities in stabilizing radiation-induced defects over geological periods.

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