Below bandgap photoluminescence of an AlN crystal: Co-existence of two different charging states of a defect center
The below bandgap optical transitions of an aluminum nitride (AlN) crystal grown on a tungsten (W) substrate by physical vapor transport (PVT) are investigated by below-bandgap-excited photoluminescence (PL) spectroscopy and first-principles calculations. Oxygen (O) is the only impurity in the AlN-o...
| Main Authors: | , , , , , , , |
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| Format: | Article |
| Language: | English |
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AIP Publishing LLC
2020-08-01
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| Series: | APL Materials |
| Online Access: | http://dx.doi.org/10.1063/5.0012685 |
| _version_ | 1818039807621726208 |
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| author | Qin Zhou Zhaofu Zhang Hui Li Sergii Golovynskyi Xi Tang Honglei Wu Jiannong Wang Baikui Li |
| author_facet | Qin Zhou Zhaofu Zhang Hui Li Sergii Golovynskyi Xi Tang Honglei Wu Jiannong Wang Baikui Li |
| author_sort | Qin Zhou |
| collection | DOAJ |
| description | The below bandgap optical transitions of an aluminum nitride (AlN) crystal grown on a tungsten (W) substrate by physical vapor transport (PVT) are investigated by below-bandgap-excited photoluminescence (PL) spectroscopy and first-principles calculations. Oxygen (O) is the only impurity in the AlN-on-W crystal grown by PVT. By analyzing the excitation-power-, excitation-photon-energy-, and temperature-dependence of the PL spectra, the emission peaks of defect complexes involving aluminum vacancy (VAl) and substitutional oxygen (ON) with different spatial and atomic configurations, i.e., VAl–ON and VAl–2ON with ON featuring axial or basal configurations, are identified. It is revealed that two different charging states coexist in thermal equilibrium for each configuration of VAl–ON complexes. The optical transitions between the conduction band and (VAl–ON)2− and/or (VAl–2ON)1− contribute the UV emissions and those between the valence band and (VAl–ON)1− or (VAl–2ON)0 contribute the red emissions. |
| first_indexed | 2024-12-10T08:04:30Z |
| format | Article |
| id | doaj.art-a1756f996f0d4221958559905c9aa06d |
| institution | Directory Open Access Journal |
| issn | 2166-532X |
| language | English |
| last_indexed | 2024-12-10T08:04:30Z |
| publishDate | 2020-08-01 |
| publisher | AIP Publishing LLC |
| record_format | Article |
| series | APL Materials |
| spelling | doaj.art-a1756f996f0d4221958559905c9aa06d2022-12-22T01:56:43ZengAIP Publishing LLCAPL Materials2166-532X2020-08-0188081107081107-810.1063/5.0012685Below bandgap photoluminescence of an AlN crystal: Co-existence of two different charging states of a defect centerQin Zhou0Zhaofu Zhang1Hui Li2Sergii Golovynskyi3Xi Tang4Honglei Wu5Jiannong Wang6Baikui Li7Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province, College of Physics and Optoelectronic Engineering, Shenzhen University, Nanhai Ave., 3688 Shenzhen, ChinaDepartment of Engineering, University of Cambridge, CB2 1PZ Cambridge, United KingdomDepartment of Physics, The Hong Kong University of Science and Technology, Hong Kong, ChinaKey Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province, College of Physics and Optoelectronic Engineering, Shenzhen University, Nanhai Ave., 3688 Shenzhen, ChinaKey Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province, College of Physics and Optoelectronic Engineering, Shenzhen University, Nanhai Ave., 3688 Shenzhen, ChinaKey Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province, College of Physics and Optoelectronic Engineering, Shenzhen University, Nanhai Ave., 3688 Shenzhen, ChinaDepartment of Physics, The Hong Kong University of Science and Technology, Hong Kong, ChinaKey Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province, College of Physics and Optoelectronic Engineering, Shenzhen University, Nanhai Ave., 3688 Shenzhen, ChinaThe below bandgap optical transitions of an aluminum nitride (AlN) crystal grown on a tungsten (W) substrate by physical vapor transport (PVT) are investigated by below-bandgap-excited photoluminescence (PL) spectroscopy and first-principles calculations. Oxygen (O) is the only impurity in the AlN-on-W crystal grown by PVT. By analyzing the excitation-power-, excitation-photon-energy-, and temperature-dependence of the PL spectra, the emission peaks of defect complexes involving aluminum vacancy (VAl) and substitutional oxygen (ON) with different spatial and atomic configurations, i.e., VAl–ON and VAl–2ON with ON featuring axial or basal configurations, are identified. It is revealed that two different charging states coexist in thermal equilibrium for each configuration of VAl–ON complexes. The optical transitions between the conduction band and (VAl–ON)2− and/or (VAl–2ON)1− contribute the UV emissions and those between the valence band and (VAl–ON)1− or (VAl–2ON)0 contribute the red emissions.http://dx.doi.org/10.1063/5.0012685 |
| spellingShingle | Qin Zhou Zhaofu Zhang Hui Li Sergii Golovynskyi Xi Tang Honglei Wu Jiannong Wang Baikui Li Below bandgap photoluminescence of an AlN crystal: Co-existence of two different charging states of a defect center APL Materials |
| title | Below bandgap photoluminescence of an AlN crystal: Co-existence of two different charging states of a defect center |
| title_full | Below bandgap photoluminescence of an AlN crystal: Co-existence of two different charging states of a defect center |
| title_fullStr | Below bandgap photoluminescence of an AlN crystal: Co-existence of two different charging states of a defect center |
| title_full_unstemmed | Below bandgap photoluminescence of an AlN crystal: Co-existence of two different charging states of a defect center |
| title_short | Below bandgap photoluminescence of an AlN crystal: Co-existence of two different charging states of a defect center |
| title_sort | below bandgap photoluminescence of an aln crystal co existence of two different charging states of a defect center |
| url | http://dx.doi.org/10.1063/5.0012685 |
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