Deep-level traps in lightly Si-doped n-GaN on free-standing m-oriented GaN substrates
In this study, we investigated the deep-level traps in Si-doped GaN epitaxial layers by metal-organic chemical vapor deposition on c-oriented and m-oriented free-standing GaN substrates. The c-oriented and m-oriented epitaxial layers, grown at a temperature of 1000 °C and V/III ratio of 1000, contai...
| Main Authors: | , , , , |
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| Format: | Article |
| Language: | English |
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AIP Publishing LLC
2018-04-01
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| Series: | AIP Advances |
| Online Access: | http://dx.doi.org/10.1063/1.5011362 |
| _version_ | 1819118425970049024 |
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| author | H. Yamada H. Chonan T. Takahashi T. Yamada M. Shimizu |
| author_facet | H. Yamada H. Chonan T. Takahashi T. Yamada M. Shimizu |
| author_sort | H. Yamada |
| collection | DOAJ |
| description | In this study, we investigated the deep-level traps in Si-doped GaN epitaxial layers by metal-organic chemical vapor deposition on c-oriented and m-oriented free-standing GaN substrates. The c-oriented and m-oriented epitaxial layers, grown at a temperature of 1000 °C and V/III ratio of 1000, contained carbon atomic concentrations of 1.7×1016 and 4.0×1015 cm–3, respectively. A hole trap was observed at about 0.89 eV above the valence band maximum by minority carrier transient spectroscopy. The trap concentrations in the c-oriented and m-oriented GaN epitaxial layers were consistent with the carbon atomic concentrations from secondary ion mass spectroscopy and the yellow luminescence intensity at 2.21 eV from photoluminescence. The trap concentrations in the m-oriented GaN epitaxial layers were lower than those in the c-oriented GaN. Two electron traps, 0.24 and 0.61 eV below the conduction band (EC) minimum, were observed in the c-oriented GaN epitaxial layer. In contrast, the m-oriented GaN epitaxial layer was free from the electron trap at EC – 0.24 eV, and the trap concentration at EC – 0.61 eV in the m-oriented GaN epitaxial layer was lower than that in the c-oriented GaN epitaxial layer. The m-oriented GaN epitaxial layer exhibited fewer hole and electron traps compared to the c-oriented GaN epitaxial layers. |
| first_indexed | 2024-12-22T05:48:41Z |
| format | Article |
| id | doaj.art-3ab1e54178a7489b910ecff8f286c250 |
| institution | Directory Open Access Journal |
| issn | 2158-3226 |
| language | English |
| last_indexed | 2024-12-22T05:48:41Z |
| publishDate | 2018-04-01 |
| publisher | AIP Publishing LLC |
| record_format | Article |
| series | AIP Advances |
| spelling | doaj.art-3ab1e54178a7489b910ecff8f286c2502022-12-21T18:36:57ZengAIP Publishing LLCAIP Advances2158-32262018-04-0184045311045311-910.1063/1.5011362049804ADVDeep-level traps in lightly Si-doped n-GaN on free-standing m-oriented GaN substratesH. Yamada0H. Chonan1T. Takahashi2T. Yamada3M. Shimizu4National Institute of Advanced Industrial Science and Technology, GaN-OIL, Nagoya, Aichi 464-8601, JapanNational Institute of Advanced Industrial Science and Technology, ADPERC, Tsukuba, Ibaraki 805-8501, JapanNational Institute of Advanced Industrial Science and Technology, ADPERC, Tsukuba, Ibaraki 805-8501, JapanNational Institute of Advanced Industrial Science and Technology, GaN-OIL, Nagoya, Aichi 464-8601, JapanNational Institute of Advanced Industrial Science and Technology, GaN-OIL, Nagoya, Aichi 464-8601, JapanIn this study, we investigated the deep-level traps in Si-doped GaN epitaxial layers by metal-organic chemical vapor deposition on c-oriented and m-oriented free-standing GaN substrates. The c-oriented and m-oriented epitaxial layers, grown at a temperature of 1000 °C and V/III ratio of 1000, contained carbon atomic concentrations of 1.7×1016 and 4.0×1015 cm–3, respectively. A hole trap was observed at about 0.89 eV above the valence band maximum by minority carrier transient spectroscopy. The trap concentrations in the c-oriented and m-oriented GaN epitaxial layers were consistent with the carbon atomic concentrations from secondary ion mass spectroscopy and the yellow luminescence intensity at 2.21 eV from photoluminescence. The trap concentrations in the m-oriented GaN epitaxial layers were lower than those in the c-oriented GaN. Two electron traps, 0.24 and 0.61 eV below the conduction band (EC) minimum, were observed in the c-oriented GaN epitaxial layer. In contrast, the m-oriented GaN epitaxial layer was free from the electron trap at EC – 0.24 eV, and the trap concentration at EC – 0.61 eV in the m-oriented GaN epitaxial layer was lower than that in the c-oriented GaN epitaxial layer. The m-oriented GaN epitaxial layer exhibited fewer hole and electron traps compared to the c-oriented GaN epitaxial layers.http://dx.doi.org/10.1063/1.5011362 |
| spellingShingle | H. Yamada H. Chonan T. Takahashi T. Yamada M. Shimizu Deep-level traps in lightly Si-doped n-GaN on free-standing m-oriented GaN substrates AIP Advances |
| title | Deep-level traps in lightly Si-doped n-GaN on free-standing m-oriented GaN substrates |
| title_full | Deep-level traps in lightly Si-doped n-GaN on free-standing m-oriented GaN substrates |
| title_fullStr | Deep-level traps in lightly Si-doped n-GaN on free-standing m-oriented GaN substrates |
| title_full_unstemmed | Deep-level traps in lightly Si-doped n-GaN on free-standing m-oriented GaN substrates |
| title_short | Deep-level traps in lightly Si-doped n-GaN on free-standing m-oriented GaN substrates |
| title_sort | deep level traps in lightly si doped n gan on free standing m oriented gan substrates |
| url | http://dx.doi.org/10.1063/1.5011362 |
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