Characterization of vacancy defects in Cu(In,Ga)Se2 by positron annihilation spectroscopy
The photovoltaic performance of Cu(In1-x,Gax)Se2 (CIGS) materials is commonly assumed to be degraded by the presence of vacancy-related defects. However, experimental identification of specific vacancy defects remains challenging. In this work we report positron lifetime measurements on CIGS crystal...
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| Format: | Article |
| Language: | English |
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AIP Publishing LLC
2016-12-01
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| Series: | AIP Advances |
| Online Access: | http://dx.doi.org/10.1063/1.4972251 |
| _version_ | 1818909947036958720 |
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| author | M. R. M. Elsharkawy G. S. Kanda M. V. Yakushev E. E. Abdel-Hady D. J. Keeble |
| author_facet | M. R. M. Elsharkawy G. S. Kanda M. V. Yakushev E. E. Abdel-Hady D. J. Keeble |
| author_sort | M. R. M. Elsharkawy |
| collection | DOAJ |
| description | The photovoltaic performance of Cu(In1-x,Gax)Se2 (CIGS) materials is commonly assumed to be degraded by the presence of vacancy-related defects. However, experimental identification of specific vacancy defects remains challenging. In this work we report positron lifetime measurements on CIGS crystals with x = 0, and x = 0.05, saturation trapping to two dominant vacancy defect types, in both types of crystal, is observed and found to be independent of temperature between 15–300 K. Atomic superposition method calculations of the positron lifetimes for a range of vacancy defects in CIS and CGS are reported. The calculated lifetimes support the assignment of the first experimental lifetime component to monovacancy or divacancy defects, and the second to trivacancies, or possibly the large In-Se divacancy. Further, the calculated positron parameters obtained here provide evidence that positron annihilation spectroscopy has the capability to identify specific vacancy-related defects in the Cu(In1-x,Gax)Se2 chalcogenides. |
| first_indexed | 2024-12-19T22:35:00Z |
| format | Article |
| id | doaj.art-725b1ee54cb04d2d9e4277f7fc52cda0 |
| institution | Directory Open Access Journal |
| issn | 2158-3226 |
| language | English |
| last_indexed | 2024-12-19T22:35:00Z |
| publishDate | 2016-12-01 |
| publisher | AIP Publishing LLC |
| record_format | Article |
| series | AIP Advances |
| spelling | doaj.art-725b1ee54cb04d2d9e4277f7fc52cda02022-12-21T20:03:14ZengAIP Publishing LLCAIP Advances2158-32262016-12-01612125031125031-810.1063/1.4972251034612ADVCharacterization of vacancy defects in Cu(In,Ga)Se2 by positron annihilation spectroscopyM. R. M. Elsharkawy0G. S. Kanda1M. V. Yakushev2E. E. Abdel-Hady3D. J. Keeble4Carnegie Laboratory of Physics, SUPA, School of Science and Engineering, University of Dundee, Dundee DD1 4HN, United KingdomCarnegie Laboratory of Physics, SUPA, School of Science and Engineering, University of Dundee, Dundee DD1 4HN, United KingdomUral Federal University, Ekaterinburg 620002, RussiaPhysics Department, Faculty of Science, Minia University, P.O. Box 61519, Minia, EgyptCarnegie Laboratory of Physics, SUPA, School of Science and Engineering, University of Dundee, Dundee DD1 4HN, United KingdomThe photovoltaic performance of Cu(In1-x,Gax)Se2 (CIGS) materials is commonly assumed to be degraded by the presence of vacancy-related defects. However, experimental identification of specific vacancy defects remains challenging. In this work we report positron lifetime measurements on CIGS crystals with x = 0, and x = 0.05, saturation trapping to two dominant vacancy defect types, in both types of crystal, is observed and found to be independent of temperature between 15–300 K. Atomic superposition method calculations of the positron lifetimes for a range of vacancy defects in CIS and CGS are reported. The calculated lifetimes support the assignment of the first experimental lifetime component to monovacancy or divacancy defects, and the second to trivacancies, or possibly the large In-Se divacancy. Further, the calculated positron parameters obtained here provide evidence that positron annihilation spectroscopy has the capability to identify specific vacancy-related defects in the Cu(In1-x,Gax)Se2 chalcogenides.http://dx.doi.org/10.1063/1.4972251 |
| spellingShingle | M. R. M. Elsharkawy G. S. Kanda M. V. Yakushev E. E. Abdel-Hady D. J. Keeble Characterization of vacancy defects in Cu(In,Ga)Se2 by positron annihilation spectroscopy AIP Advances |
| title | Characterization of vacancy defects in Cu(In,Ga)Se2 by positron annihilation spectroscopy |
| title_full | Characterization of vacancy defects in Cu(In,Ga)Se2 by positron annihilation spectroscopy |
| title_fullStr | Characterization of vacancy defects in Cu(In,Ga)Se2 by positron annihilation spectroscopy |
| title_full_unstemmed | Characterization of vacancy defects in Cu(In,Ga)Se2 by positron annihilation spectroscopy |
| title_short | Characterization of vacancy defects in Cu(In,Ga)Se2 by positron annihilation spectroscopy |
| title_sort | characterization of vacancy defects in cu in ga se2 by positron annihilation spectroscopy |
| url | http://dx.doi.org/10.1063/1.4972251 |
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