Very slow decay of a defect related emission band at 2.4 eV in AlN: Signatures of the Si related shallow DX state
Autor: | Christiane Grund, Ramon Collazo, Klaus Thonke, Zachary Bryan, Benjamin Neuschl, Zlatko Sitar, Matthias Lamprecht |
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Rok vydání: | 2016 |
Předmět: |
010302 applied physics
Photoluminescence Silicon Chemistry Wide-bandgap semiconductor General Physics and Astronomy chemistry.chemical_element 02 engineering and technology Nitride 021001 nanoscience & nanotechnology 01 natural sciences law.invention law 0103 physical sciences Atomic physics 0210 nano-technology Luminescence Electron paramagnetic resonance Shallow donor Excitation |
Zdroj: | Journal of Applied Physics. 119:155701 |
ISSN: | 1089-7550 0021-8979 |
Popis: | We report on a defect related luminescence band at 2.4 eV in aluminum nitride bulk crystals, for which we find strong indications to be related to silicon DX centers. Time resolved photoluminescence spectroscopy using a sub-bandgap excitation reveals two different recombination processes with very long decay times of 13 ms and 153 ms at low temperature. Based on the results of temperature and excitation dependent photoluminescence experiments, the process with the shorter lifetime is assigned to a donor-acceptor pair transition involving the shallow silicon donor state, which can be emptied with a thermal dissociation energy of 65 meV. The slower process with a thermal quenching energy of 15 meV is assigned to the slightly deeper Si DX state known from electron paramagnetic resonance experiments, which is transferred back to the shallow donor state. |
Databáze: | OpenAIRE |
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