Deep Levels in 4H Silicon Carbide Epilayers Induced by Neutron-Irradiation up to 1016 n/cm2

AbstractWe investigated the electronic levels of defects introduced in 4H-SiC α-particle detectors by irradiation with 1 MeV neutrons up to a fluence equal to 8x1015 n/cm2. As well, we investigated their effect on the detector radiation hardness. This study was carried out by deep level transient spectroscopy (DLTS) and photo-induced current transient spectroscopy (PICTS). As the irradiation level approaches fluences in the order of 1015 n/cm2, the material behaves as highly resistive due to a very great compensation effect but the diodes are still able to detect with a acceptably good charge collection efficiency (CCE) equal to 80%. By further increasing fluence, CCE decreases reaching the value of ≈ 20% at fluence of 8x1015 n/cm2.The dominant peaks in the PICTS spectra occur in the temperature range [400, 700] K. Enthalpy, capture cross-section and order of magnitude of the density of such deep levels were calculated. In the above said temperature range the deep levels associated to the radiation induced defects play the key role in the degradation of the CCE. Two deep levels at Et = 1.18 eV and Et = 1.50 eV are likely to be responsible of such dramatic decrease of the charge collection efficiency. These levels were reasonably associated to an elementary defect involving a carbon vacancy and to a defect complex involving a carbon and a silicon vacancy, respectively.

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Process-Induced Defects in High-Purity GaAs

MRS Proceedings ◽

10.1557/proc-14-283 ◽

1982 ◽

Vol 14 ◽

Cited By ~ 1

Author(s):

P. H. Campbell ◽

O. Aina ◽

B. J. Baliga ◽

R. Ehle

Keyword(s):

High Temperature ◽

High Purity ◽

Deep Level Transient Spectroscopy ◽

Deep Level ◽

Deep Levels ◽

Schottky Contacts ◽

High Temperature Annealing ◽

Order Of Magnitude ◽

Transient Spectroscopy ◽

Induced Defects

ABSTRACTHigh temperature annealing of Si 3 N4 and SiO2 capped high purity LPE GaAs is shown to result in a reduction in the surface carrier concentration by about an order of magnitude. Au Schottky contacts made on the annealed samples were found to have severely degraded breakdown characteristics. Using deep level transient spectroscopy, deep levels at EC–.58eV, EC–.785eV were detected in the SiO2, capped samples and EC–.62eV, EC–.728eV in the Si3N4 capped Samples while none was detected in the unannealed samples.The electrical degradations are explained in terms of compensation mechanisns and depletion layer recombination-generation currents due to the deep levels.

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Defects in an Electron-Irradiated 6H-SiC Diode Studied by Alpha Particle Induced Charge Transient Spectroscopy: Their Impact on the Degraded Charge Collection Efficiency

Materials Science Forum ◽

10.4028/www.scientific.net/msf.717-720.267 ◽

2012 ◽

Vol 717-720 ◽

pp. 267-270

Author(s):

Naoya Iwamoto ◽

Atsushi Koizumi ◽

Shinobu Onoda ◽

Takahiro Makino ◽

Takeshi Ohshima ◽

...

Keyword(s):

Alpha Particle ◽

Deep Level ◽

Collection Efficiency ◽

High Energy ◽

Electron Trap ◽

Charge Collection ◽

High Energy Electron ◽

Charge Collection Efficiency ◽

Induced Charge ◽

Transient Spectroscopy

Defects in electron-irradiated 6H-SiC diodes have been studied by single alpha particle induced charge transient spectroscopy and deep level transient spectroscopy (DLTS) in order to identify critical defects responsible for the charge collection efficiency (CCE) decreased by high-energy electron irradiation. The defect X2 detected by the charge transient spectroscopy and the electron trap Ei detected by the DLTS had a similar activation energy of around 0.50 eV. In addition, the annealing at 200oC completely removed defects X2 and Ei, and restored the CCE. The defect X2 is attributed to the electron trap Ei, and responsible for the decreased CCE.

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“Recovery” Effect of Electron Induced Damage in 4H-SiC Schottky Diodes

MRS Proceedings ◽

10.1557/proc-792-r10.6 ◽

2003 ◽

Vol 792 ◽

Cited By ~ 1

Author(s):

A. Castaldini ◽

A. Cavallini ◽

L. Rigutti ◽

F. Nava ◽

P.G. Fuochi ◽

...

Keyword(s):

Deep Level ◽

Collection Efficiency ◽

Schottky Diodes ◽

Chemical Vapour ◽

Liquid Nitrogen Temperature ◽

Charge Collection Efficiency ◽

Before And After ◽

Transient Spectroscopy ◽

Lower Temperature ◽

Different Doses

ABSTRACTThe effects of electron irradiation on the defects associated electronic levels in Schottky diodes on 4H silicon carbide epilayers grown by chemical vapour deposition were investigated by Deep Level Transient Spectroscopy (DLTS) and Capacitance-Voltage (C-V) characteristics. These investigations were performed before and after irradiation with 8.6 MeV electrons at different doses. After irradiation four new traps with enthalpies equal to (Ec-0.23 eV), (Ec-0.39 eV), (Ec-0.63 eV) and (Ec-0.75 eV) were detected. Their thermal stability, a key point to determine their structure on the basis of recent theoretical and experimental results, was carefully investigated since it was earlier observed that during DLTS temperature runs up to 500 K a slight but significant recovery of a few irradiation-induced levels occurs. This effect was previously observed in literature for the level (Ec-0.70 eV) after thermal treatment at 500 °C [1], but the present results indicate that it involves more than a single level and is also effective at lower temperature. DLTS analyses were also performed from room temperature to liquid nitrogen temperature and vice versa up to 500 K.The annealing kinetics is reported and a few conclusions on the structure of the defects involved in the recovery are drawn. The correlation with the diode charge collection efficiency is also reported.

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CW Laser Induced Deep Level Defects in Virgin Silicon.

MRS Proceedings ◽

10.1557/proc-4-325 ◽

1981 ◽

Vol 4 ◽

Cited By ~ 1

Author(s):

A. Chantre ◽

M. Kechouane ◽

D. Bois

Keyword(s):

High Temperature ◽

Point Defects ◽

Deep Level Transient Spectroscopy ◽

Solid Phase ◽

Deep Level ◽

Deep Levels ◽

Cw Laser ◽

Temperature State ◽

Transient Spectroscopy ◽

Induced Defects

ABSTRACTDeep Level Transient Spectroscopy has been used to investigate cw laser induced defects in virgin silicon. Two main regimes have been found. In the solid phase regime, two well defined deep levels at Ec−0.19 eV and Ec−0.45 eV are observed. This point defect introduction is proposed to be involved in the degradation of ion-implanted cw laser annealed junctions. The mechanism leading to point defects generation is likely to involve trapping of in–diffused vacancies, quenched–in from the high temperature state. In the slip lines or melt regimes, additionnal deep levels are detected, which are ascribed to dislocations.

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Annealing Kinetics during Rapid and Classical Thermal Processing of Laser and Implantation Induced defects in Silicon

MRS Proceedings ◽

10.1557/proc-74-699 ◽

1986 ◽

Vol 74 ◽

Author(s):

W. O. Adekoya ◽

J. C. Muller ◽

P. Siffert

Keyword(s):

Deep Level ◽

Strong Support ◽

Furnace Annealing ◽

Type Silicon ◽

Defect Annealing ◽

Thermal Mechanism ◽

Order Of Magnitude ◽

Transient Spectroscopy ◽

P Type ◽

Induced Defects

AbstractThe annealing behaviour of electrically-active defects in-duced in virgin n-type silicon by-Nd-Yag Laser (1.6 J cm−2,0.53 μm) irradiation has been investigated with Deep Level Transient Spectroscopy (DLTS). The observed defects : E(0.32 eV), E(0.45 eV) and E(0.53 eV) are characteristic of laser treated silicon, and have been reported by a number of workers. Using a rapid thermal furnace at 600°C for durations between 10 and 60s, we have observed a linear decrease in the concentration of these defects, and for times T > 60s, they are seen to disappear. A similar result was obtained in studies carried out on both vir-gin and implanted p-type silicon. This is in sharp contrast to the classical furnace annealing which requires much longer du-rations (20–30 min) at the same temperature (600 °C) in order to obtain the same results. A study of the annealing kinetics for the E(0.32 eV ;σn = 8 × 10−16 cm−2) level between 500 and 650°C in steps of 50°C for the two processes confirms this tendency for all processing temperatures, and shows a difference in ac-tivation energy of practically the same order of magnitude as the ionization energy of the defect (i.e. = 0.31 eV). Induced defects in high temperature > 1000°C in rapid thermal processed (RTA) n-type Si, also annealed out after a further 600°650 °C, 60 s RTA treatment. These results suggest that defect annealing is not a purely thermal mechanism, and lend strong support to the idea of an ionization induced enhancement.

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Effects of radiation-induced defects on the charge collection efficiency of a silicon carbide particle detector

10.1117/12.2016464 ◽

2013 ◽

Author(s):

Naoya Iwamoto ◽

Shinobu Onoda ◽

Takahiro Makino ◽

Takeshi Ohshima ◽

Kazutoshi Kojima ◽

...

Keyword(s):

Silicon Carbide ◽

Carbide Particle ◽

Collection Efficiency ◽

Charge Collection ◽

Particle Detector ◽

Charge Collection Efficiency ◽

Silicon Carbide Particle ◽

Radiation Induced ◽

Effects Of Radiation ◽

Induced Defects

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EXPERIMENTAL VERIFICATION OF DLTS MODELS

CAD/EDA, MODELING AND SIMULATION IN MODERN ELECTRONICS: COLLECTION OF SCIENTIFIC PAPERS OF THE III INTERNATIONAL SCIENTIFIC AND PRACTICAL CONFERENCE ◽

10.30987/conferencearticle_5e028210b72ba9.48046910 ◽

2019 ◽

Author(s):

Nataliya Mitina ◽

Vladimir Krylov

Keyword(s):

Activation Energy ◽

Gallium Arsenide ◽

Data Processing ◽

Experimental Verification ◽

Deep Level ◽

Deep Levels ◽

Transient Spectroscopy

The results of an experiment to determine the activation energy of a deep level in a gallium arsenide mesastructure, obtained by the method of capacitive deep levels transient spectroscopy with data processing according to the Oreshkin model and Lang model, are considered.

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