Lithium related deep and shallow acceptors in Li-doped ZnO nanocrystals

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Rauch C., Gehlhoff W., Wagner M. R., Malguth E., Callsen G., Kirste R., ...Daha Fazla

JOURNAL OF APPLIED PHYSICS, cilt.107, sa.2, 2010 (SCI-Expanded) identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 107 Sayı: 2
  • Basım Tarihi: 2010
  • Doi Numarası: 10.1063/1.3275889
  • Dergi Adı: JOURNAL OF APPLIED PHYSICS
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Anahtar Kelimeler: deep levels, Fermi level, II-VI semiconductors, impurity distribution, lithium, nanostructured materials, paramagnetic resonance, photoluminescence, semiconductor doping, valence bands, wide band gap semiconductors, zinc compounds, ZINC-OXIDE
  • Akdeniz Üniversitesi Adresli: Hayır

Özet

We study the existence of Li-related shallow and deep acceptor levels in Li-doped ZnO nanocrystals using electron paramagnetic resonance (EPR) and photoluminescence (PL) spectroscopy. ZnO nanocrystals with adjustable Li concentrations between 0% and 12% have been prepared using organometallic precursors and show a significant lowering of the Fermi energy upon doping. The deep Li acceptor with an acceptor energy of 800 meV could be identified in both EPR and PL measurements and is responsible for the yellow luminescence at 2.2 eV. Additionally, a shallow acceptor state at 150 meV above the valence band maximum is made responsible for the observed donor-acceptor pair and free electron-acceptor transitions at 3.235 and 3.301 eV, possibly stemming from the formation of Li-related defect complexes acting as acceptors.

We study the existence of Li-related shallow and deep acceptor levels in Li-doped ZnO nanocrystals using electron paramagnetic resonance (EPR) and photoluminescence (PL) spectroscopy. ZnO nanocrystals with adjustable Li concentrations between 0% and 12% have been prepared using organometallic precursors and show a significant lowering of the Fermi energy upon doping. The deep Li acceptor with an acceptor energy of 800 meV could be identified in both EPR and PL measurements and is responsible for the yellow luminescence at 2.2 eV. Additionally, a shallow acceptor state at 150 meV above the valence band maximum is made responsible for the observed donor-acceptor pair and free electron-acceptor transitions at 3.235 and 3.301 eV, possibly stemming from the formation of Li-related defect complexes acting as acceptors.