V. Lashkaryov Institute of Semiconductor Physics, NAS of Ukraine, 41, prospect Nauky, Kyiv 03028, Ukraine Phone: +38(044)525-72-34; e-mail: stara_t@ukr.net

Abstract. Defect related emission in undoped and doped with manganese ZnO ceramics was investigated. Mn concentration NMn was varied from 1019 to 1021 cm–3.The samples were sintered for 3 hours in air at 1100 °C. The color of ZnO:Mn ceramics changed from yellow to reddish-brown with increasing the Mn content. Photoluminescence (PL) spectra of prepared samples were measured at room temperature and analyzed by Gaussian fitting. PL of undoped ceramics exhibited itself as intense broad band peaking at about 550 nm. Two effects were shown to occur as a result of Mn doping: i) drastic quenching of self-activated PL accompanied by gradual red-shift of spectral boundary of the quenching with increasing the Mn content; ii) appearance of a new emission band peaking at 645 nm that becomes dominant in the PL spectrum at NMn = 1020 cm–3. The observed effects were believed to be due to re-absorption of self-activated ZnO emission by Mn-related centers. The following recombination in excited centers was supposed to occur by both radiative and nonradiative ways, the former being responsible for 645 nm PL band.

Keywords: ZnO ceramics, photoluminescence.

Full Text (PDF)

References

Back to Volume 20 N1