Influence of annealing in Zn vapor on the luminescence of MgZnO ceramics. Issue 9 (7th May 2014)

• Record Type: Journal Article
• Authors: Markevich, I.; Stara, T.; Kolomys, O.; Romanyuk, A. S.; Strelchuk, V.
• Is Part Of: Physica status solidi. Volume 11:Issue 9/10(2014)
• Page Start: 1485
• Page End: 1487
• Publication Date: 2014-05-07
• Subjects: Solid state physics -- Congresses; Solid state physics -- Periodicals; Solid state physics; Conference proceedings; Periodicals; 530.41
• DOI: 10.1002/pssc.201300647
• Languages: English
• ISSNs: 1862-6351

Abstract

<abstract abstract-type="main" xml:lang="en"> <title>Abstract</title> <p>ZnO‐based compounds that exhibit a number of strongly overlapping emission bands in visible spectral region are promising materials for white‐light emitters with continuous emission spectrum. Defect‐related emission in doped with different impurities ZnO, however, spreads from green to red spectral region, so its shift toward shorter wavelengths is required. We supposed that this problem can be solved due to broadening of ZnO band gap by alloying ZnO with MgO. The enhancement of visible emission brightness is also an important problem. In this work, Mg<sub>x</sub>Zn<sub>1‐x</sub>O ceramics with x =0 and x=0.2 were sintered both in air and Zn vapor at 950<sup> o</sup>C. Emission and Raman scattering spectra were measured at 300 K using 325 nm line of He‐Cd laser as excitation source. In samples sintered in air, bright UV emission and weak visible one took place, adding MgO to ZnO resulting in blue‐shift of the latter. Sintering in Zn vapor was found to weaken UV emission and to increase drastically the brightness of visible one especially in blue‐green spectral region. As a result, bright blue radiation was observed from MgZnO ceramics under excitation by considerably week UV light. Obtained effects were accounted for by the shift of "green" centers energetic level with respect to involved band edge as a result of band‐gap broadening and by the increase of this center density due to annealing in Zn vapor. (© 2014 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)</p> </abstract>