Atomic Layer Deposition of MgO Nanofilms on BaMgAl10O17 : Eu2+ Blue Phosphors

This paper reports the growth of MgO nanofilms on BaMgAl10O17:Eu2+ blue phosphors by using the atomic layer deposition method. MgO films were prepared at 120°C by using Mg(CpEt)2 and H2O as the precursor and reactant gas, respectively. X-ray photoelectron spectroscopy (XPS) analysis showed that the Mg peak of the coated powders was higher than that of the uncoated powders. This confirmed that the surface of the coated phosphor powder comprised MgO nanoscale film. Through TEM and FE-SEM analysis, it was observed that the growth rate was about 0.33 Å/cycle and that the surface morphology of the coated phosphors was smoother and clearer than that of uncoated phosphor. The photoluminescence (PL) intensity for the coated phosphors was 5%–19% higher than that of uncoated phosphor. This means that the reactive surface is uniformly grown with stable magnesium oxide to reduce the dead surface layer without change of bulk properties.