The Behavior of Oxygen and Defects in Si-Based Semiconductor Studied by Positron Annihilation Techniques

Slow positron beam and coincidence Doppler broadening techniques have been used to follow temperature-induced defects and structural changes in Cz-Si with an initial oxygen content of 1.1×1018 cm-3. Oxygen is recognized as a peak at about 11.85×10-3m0c on the ratio curves. For Cz-Si annealed at 480 oC/15h or 600 oC/15h, the ratio curves show the presence of vacancy-like defects, but they are not associated with oxygen. For Cz-Si annealed at 480 oC/15h, then followed by a 600 oC/15h heat treatment, the ratio curves show the signal of O atom. The ratio curves of Cz-Si, thermally treated by a two-step (480oC/15h + 600oC/15h) pre-annealing, followed by a one-step annealing under different hydrostatic argon pressures and annealed temperatures, also show a peak at 11.85×10-3m0c. The height of the peak varies with different samples. Experimental results indicate that the SiO2 film will form on the surface of Cz-Si after the heat treatment.

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Studying of 2D Titanium Carbide Structure by Raman Spectroscopy after Heat Treatment in Argon and Hydrogen Atmospheres

Eurasian Chemico-Technological Journal ◽

10.18321/ectj194 ◽

2017 ◽

Vol 19 (2) ◽

pp. 181 ◽

Cited By ~ 5

Author(s):

Olzhas Kaipoldayev ◽

Ye. Mukhametkarimov ◽

Renata Nemkaeva ◽

G. Baigarinova ◽

Madi Aitzhanov ◽

...

Keyword(s):

Heat Treatment ◽

Raman Spectroscopy ◽

Titanium Carbide ◽

Functional Groups ◽

Optimal Regime ◽

Heat Treated ◽

Initial Oxygen Content ◽

Initial Oxygen ◽

Tio2 Rutile ◽

Total Disappearance

Herein we show the effect of heat treatment of two dimensional layered titanium carbide structure (Ti3C2Tx), so called MXene. As prepared MXene has functional groups -OH, -F, -Cl. In order to remove the functional groups we heat treated the MXene in Ar (with 0.01% O2) and H2 (with 0.01% H2O) atmospheres. We discovered the significant decrease in the amount of functional groups (-F and -Cl) and increase in the -O content, which refers to the oxidation of the material. Also we determined the optimal regime for Raman spectroscopy in order to avoid any changes in the structure of the material. We revealed that titanium carbide changes its structure at 700 °C and 900 °C into two different titanium dioxide modifications like rutile and anatase in Ar (with 0.01% O2) atmosphere. Also there are small changes occurred in Ti3C2Tx structure and formation of amorphous carbon after 700 °C treatment in H2 (with 0.01% H2O) atmosphere and formation of TiO2 (rutile) at 900 °C. Energydispersive X-ray spectroscopy (EDX) revealed the reduction of functional groups at 700 °C in both atmospheres and total disappearance of –F and –Cl and increasing the oxygen at 900 °C. The huge increase of oxygen by atomic percent, can be explained by the initial oxygen content in argon and hydrogen gases.

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Study of Microvoids in High-Rate a-Si:H Using Positron Annihilation

MRS Proceedings ◽

10.1557/proc-467-525 ◽

1997 ◽

Vol 467 ◽

Author(s):

X. Zou ◽

D. P. Webb ◽

S. H. Lin ◽

Y. W. Lam ◽

Y. C. Chan ◽

...

Keyword(s):

Thin Films ◽

Positron Annihilation ◽

Surface Region ◽

Positron Beam ◽

High Rate ◽

Doppler Broadening ◽

Slow Positron ◽

Depth Profiles ◽

Vacancy Type Defect ◽

Low Rate

ABSTRACTIn this paper, we have carried out the positron annihilation measurement on high-rate and low-rate a-Si:H thin films deposited by PECVD. By means of the slow positron beam Doppler-broadening technique, the depth profiles of microvoids in a-Si:H have been determined. We have also studied the vacancy-type defect in the surface region in high-rate grown a-Si:H, making comparison between high-rate and low-rate a-Si:H. By plotting S and W parameters in the (S, W) plane, we have shown that the vacancies in all of the high-rate and low-rate deposited intrinsic samples, and in differently doped low-rate samples are of the same nature.

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Ion-Implantation Induced Defects in ZnO Studied by a Slow Positron Beam

Materials Science Forum ◽

10.4028/www.scientific.net/msf.445-446.57 ◽

2004 ◽

Vol 445-446 ◽

pp. 57-59 ◽

Cited By ~ 3

Author(s):

Z.Q. Chen ◽

Masaki Maekawa ◽

Takashi Sekiguchi ◽

Ryoichi Suzuki ◽

Atsuo Kawasuso

Keyword(s):

Ion Implantation ◽

Positron Beam ◽

Slow Positron ◽

Induced Defects

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Hydrogen-Induced Defects of Subsurface Layer in ZnO Single Crystal Probed by a Slow Positron Beam

Materials Science Forum ◽

10.4028/www.scientific.net/msf.733.232 ◽

2012 ◽

Vol 733 ◽

pp. 232-235 ◽

Cited By ~ 1

Author(s):

X.D. Xue ◽

T. Wang ◽

J. Jiang ◽

P.H. Li ◽

Y.F. Liu ◽

...

Keyword(s):

Single Crystal ◽

Subsurface Layer ◽

Positron Beam ◽

X Ray Diffraction ◽

Slow Positron ◽

X Ray ◽

S Parameter ◽

Induced Defects ◽

Zno Single Crystal ◽

Deformation Layer

Hydrogen-induced defects of ZnO single crystals electrochemically charged with hydrogen have been investigated by positron beam-based Doppler broadening spectroscopy, X-ray diffraction (XRD) and optical microscopy (OM). XRD and OM results indicated that a deformation layer was formed due to hydrogen-induced structural change at the subsurface of ZnO single crystal. Slow positron beam measurements showed that this deformation layer contained many defects, such as dislocations and Zn vacancies, which led to increase of S parameter.

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Chemical effect of Si+ions on the implantation-induced defects in ZnO studied by a slow positron beam

Journal of Applied Physics ◽

10.1063/1.4789010 ◽

2013 ◽

Vol 113 (4) ◽

pp. 043506 ◽

Cited By ~ 3

Author(s):

M. Jiang ◽

D. D. Wang ◽

Z. Q. Chen ◽

S. Kimura ◽

Y. Yamashita ◽

...

Keyword(s):

Positron Beam ◽

Chemical Effect ◽

Slow Positron ◽

Induced Defects

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Positron Doppler broadening measurements with a LINAC-based slow positron beam

Applied Surface Science ◽

10.1016/0169-4332(94)00328-9 ◽

1995 ◽

Vol 85 ◽

pp. 172-177

Author(s):

D. Segers ◽

J. Paridaens ◽

T. Van Hoecke ◽

C. Dauwe ◽

L. Dorikens-Vanpraet ◽

...

Keyword(s):

Positron Beam ◽

Doppler Broadening ◽

Slow Positron

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Defect Detection in Fe-Cr Alloys with Positron Annihilation Doppler Broadening Spectroscopy

Materials Science Forum ◽

10.4028/www.scientific.net/msf.733.270 ◽

2012 ◽

Vol 733 ◽

pp. 270-273 ◽

Cited By ~ 2

Author(s):

Veronika Sabelová ◽

Martin Petriska ◽

Jana Veterníková ◽

Vladimir Slugeň ◽

Jarmila Degmová ◽

...

Keyword(s):

Positron Annihilation ◽

Positron Beam ◽

Quantitative Information ◽

Structural Defects ◽

Doppler Broadening ◽

Positron Energy ◽

Open Volume ◽

Order Of Magnitude ◽

Radiation Induced ◽

Induced Defects

Positron annihilation Doppler broadening spectroscopy (DBS) has been used for the detection of structural defects in Fe-9wt%Cr (Fe-9Cr) alloy in the as-prepared and implanted states. Defects were created by He and H ion implantation with a kinetic energy of 250 keV. DBS is a non-destructive method and is a unique tool for the observation of open volume defects like vacancies and vacancy clusters in solids. A positron beam with variable positron energy was used for the measurement of defect depth profiles up to 1.5 µm. The obtained results provide qualitative and semi-quantitative information about radiation induced defects and their chemical environment. Although the collision damage from helium implantation was one order of magnitude higher than for the case of hydrogen, the changes in S and W parameters are much less significant, probably due to considerably lower mobility of helium in the implanted materials, which results in helium capture by the created open volume defects.

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