Details

Autor(en) / Beteiligte

• Chen, Hui
• Gu, Shulin
• Tang, Kun
• Zhu, Shunmin
• Zhu, Zhenbang
• Ye, Jiandong
• Zhang, Rong
• Zheng, Youdou

Titel

Origins of green band emission in high-temperature annealed N-doped ZnO

Ist Teil von

• Journal of luminescence, 2011-06, Vol.131 (6), p.1189-1192

Ort / Verlag

Amsterdam: Elsevier B.V

Erscheinungsjahr

2011

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• Nitrogen-doped ZnO sample has been annealed in O 2 ambient at high temperature (1000 °C) to improve its photoluminescence property. Low-temperature photoluminescence spectra of the sample are dominated by three near-band-edge emissions at 3.377, 3.362, and 3.332 eV, which are ascribed to free exciton emission (FX A), and neutral donor-bound exciton (D 0X), and its two-electron satellite (TES), respectively. With increasing temperature in low temperature region, the intensity of FX A increases and the green band (GB) shows a negative thermal quenching effect resulting from thermal dissociation of D 0X with more free excitons and neutral donors formed. The doublet structure with energy space ∼30 meV and repeated separation of longitudinal-optical phonon energy of 72 meV are observed in GB at low temperatures. The temperature independent energy position of GB indicates a typical recombination characteristic within strongly localized complexes. The doublet structures are considered to originate from the ground and exited states of shallow donors recombining with deep acceptors such as zinc vacancies. ► Green band emission of ZnO shows doublet structures and negative thermal quenching effect. ► Doublet structures originate from ground and exited states of shallow donors to zinc vacancies. ► Negative thermal quenching effect is due to donor bound exciton dissociation. ► The origin of the green band emission is explained from another new perspective.