CdTe X/γ-ray Detectors with Different Contact Materials
Different contact materials and optimization of techniques of their depositions expand the possibilities to obtain high performance room temperature CdTe-based X/γ-ray detectors. The heterostructures with ohmic (MoO<i><sub>x</sub></i>) and Schottky (MoO<i><sub>x&l...
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MDPI AG
2021-05-01
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| Online Access: | https://www.mdpi.com/1424-8220/21/10/3518 |
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| author | Volodymyr Gnatyuk Olena Maslyanchuk Mykhailo Solovan Viktor Brus Toru Aoki |
| author_facet | Volodymyr Gnatyuk Olena Maslyanchuk Mykhailo Solovan Viktor Brus Toru Aoki |
| author_sort | Volodymyr Gnatyuk |
| collection | DOAJ |
| description | Different contact materials and optimization of techniques of their depositions expand the possibilities to obtain high performance room temperature CdTe-based X/γ-ray detectors. The heterostructures with ohmic (MoO<i><sub>x</sub></i>) and Schottky (MoO<i><sub>x</sub></i>, TiO<i><sub>x</sub></i>, TiN, and In) contacts, created by DC reactive magnetron sputtering and vacuum thermal evaporation, as well as In/CdTe/Au diodes with a <i>p-n</i> junction, formed by laser-induced doping, have been developed and investigated. Depending on the surface pre-treatment of semi-insulating <i>p</i>-CdTe crystals, the deposition of a MoO<i><sub>x</sub></i> film formed either ohmic or Schottky contacts. Based on the calculations and <i>I-V</i> characteristics of the Mo-MoO<i><sub>x</sub></i>/<i>p</i>-CdTe/MoO<i><sub>x</sub></i>-Mo, In/<i>p</i>-CdTe/MoO<i><sub>x</sub></i>-Mo, Ti-TiO<i><sub>x</sub></i>/<i>p</i>-CdTe/MoO<i><sub>x</sub></i>-Mo, and Ti-TiN/<i>p</i>-CdTe/MoO<i><sub>x</sub></i>-Mo Schottky-diode detectors, the current transport processes were described in the models of the carrier generation–recombination within the space-charge region (SCR) at low bias, and space-charge limited current incorporating the Poole–Frenkel effect at higher voltages, respectively. The energies of generation–recombination centers, density of trapping centers, and effective carrier lifetimes were determined. Nanosecond laser irradiation of the In electrode, pre-deposited on the <i>p</i>-CdTe crystals, resulted in extending the voltage range, corresponding to the carrier generation–recombination in the SCR in the <i>I-V</i> characteristics of the In/CdTe/Au diodes. Such In/CdTe/Au <i>p-n</i> junction diode detectors demonstrated high energy resolutions (7%@59.5 keV, 4%@122 keV, and 1.6%@662 keV). |
| first_indexed | 2024-03-10T11:17:08Z |
| format | Article |
| id | doaj.art-7bfeb3dd962a45699f966072b647aecb |
| institution | Directory Open Access Journal |
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| language | English |
| last_indexed | 2024-03-10T11:17:08Z |
| publishDate | 2021-05-01 |
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| spelling | doaj.art-7bfeb3dd962a45699f966072b647aecb2023-11-21T20:19:08ZengMDPI AGSensors1424-82202021-05-012110351810.3390/s21103518CdTe X/γ-ray Detectors with Different Contact MaterialsVolodymyr Gnatyuk0Olena Maslyanchuk1Mykhailo Solovan2Viktor Brus3Toru Aoki4V.E. Lashkaryov Institute of Semiconductor Physics of the National Academy of Sciences of Ukraine, Prospekt Nauky 41, 03028 Kyiv, UkraineInstitute of Applied Physics and Computer Sciences, Yuriy Fedkovych Chernivtsi National University, Kotsyubynskyi Str. 2, 58012 Chernivtsi, UkraineInstitute of Applied Physics and Computer Sciences, Yuriy Fedkovych Chernivtsi National University, Kotsyubynskyi Str. 2, 58012 Chernivtsi, UkraineDepartment of Physics, School of Sciences and Humanities, Nazarbayev University, Kabanbay Batyr Ave 53, Nur-Sultan 010000, KazakhstanResearch Institute of Electronics, Shizuoka University, 3-5-1 Johoku, Naka-ku, Hamamatsu 432 8011, JapanDifferent contact materials and optimization of techniques of their depositions expand the possibilities to obtain high performance room temperature CdTe-based X/γ-ray detectors. The heterostructures with ohmic (MoO<i><sub>x</sub></i>) and Schottky (MoO<i><sub>x</sub></i>, TiO<i><sub>x</sub></i>, TiN, and In) contacts, created by DC reactive magnetron sputtering and vacuum thermal evaporation, as well as In/CdTe/Au diodes with a <i>p-n</i> junction, formed by laser-induced doping, have been developed and investigated. Depending on the surface pre-treatment of semi-insulating <i>p</i>-CdTe crystals, the deposition of a MoO<i><sub>x</sub></i> film formed either ohmic or Schottky contacts. Based on the calculations and <i>I-V</i> characteristics of the Mo-MoO<i><sub>x</sub></i>/<i>p</i>-CdTe/MoO<i><sub>x</sub></i>-Mo, In/<i>p</i>-CdTe/MoO<i><sub>x</sub></i>-Mo, Ti-TiO<i><sub>x</sub></i>/<i>p</i>-CdTe/MoO<i><sub>x</sub></i>-Mo, and Ti-TiN/<i>p</i>-CdTe/MoO<i><sub>x</sub></i>-Mo Schottky-diode detectors, the current transport processes were described in the models of the carrier generation–recombination within the space-charge region (SCR) at low bias, and space-charge limited current incorporating the Poole–Frenkel effect at higher voltages, respectively. The energies of generation–recombination centers, density of trapping centers, and effective carrier lifetimes were determined. Nanosecond laser irradiation of the In electrode, pre-deposited on the <i>p</i>-CdTe crystals, resulted in extending the voltage range, corresponding to the carrier generation–recombination in the SCR in the <i>I-V</i> characteristics of the In/CdTe/Au diodes. Such In/CdTe/Au <i>p-n</i> junction diode detectors demonstrated high energy resolutions (7%@59.5 keV, 4%@122 keV, and 1.6%@662 keV).https://www.mdpi.com/1424-8220/21/10/3518CdTe detectorsX-ray and γ-ray spectroscopySchottky contact<i>p-n</i> junctioncharge transport mechanism |
| spellingShingle | Volodymyr Gnatyuk Olena Maslyanchuk Mykhailo Solovan Viktor Brus Toru Aoki CdTe X/γ-ray Detectors with Different Contact Materials Sensors CdTe detectors X-ray and γ-ray spectroscopy Schottky contact <i>p-n</i> junction charge transport mechanism |
| title | CdTe X/γ-ray Detectors with Different Contact Materials |
| title_full | CdTe X/γ-ray Detectors with Different Contact Materials |
| title_fullStr | CdTe X/γ-ray Detectors with Different Contact Materials |
| title_full_unstemmed | CdTe X/γ-ray Detectors with Different Contact Materials |
| title_short | CdTe X/γ-ray Detectors with Different Contact Materials |
| title_sort | cdte x γ ray detectors with different contact materials |
| topic | CdTe detectors X-ray and γ-ray spectroscopy Schottky contact <i>p-n</i> junction charge transport mechanism |
| url | https://www.mdpi.com/1424-8220/21/10/3518 |
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