Flux-Bridgman growth and characterization of Mn-doped ZnO single crystals

Mn-doped ZnO single crystals have been grown by the flux-Bridgman method from a high temperature solution of 24% ZnO-76% PbF2 (molar fraction). A fast nucleation was induced by the gas-cooling system at the bottom of the Pt crucible. A red Mn:ZnO crystal up to 13 mm×15 mm×(3–4) mm was obtained. Powder XRD patterns showed that the as-grown crystals were in wurtzite structure. Electron Probe Microanalyser (EPMA) revealed that some PbF2 inclusions formed due to fast nucleation. The additional Raman mode at 524 cm−1 was attributed to the incorporation of Mn ions into ZnO crystal. Six-line hyperfine structure was observed in the electron paramagnetic resonance (EPR) spectra, which confirmed that Mn ions occupied Zn2+ lattice sites with valence state of +2.