Naフラックス法を用いたEuドープGaNの合成および光学特性評価 Synthesis of Eu-doped GaN by the Na Flux Method and Characterization
Eu-doped GaN crystals were synthesized at 600-750°C and N<SUB>2</SUB> pressure of 5 MPa from 1 mol% Eu-added Na-Ga melts. The yield and morphology of crystals varied with temperature and Na mole fraction, <I>r</I><SUB>Na</SUB>=Na/(Na+Ga) in the melts. Colorless transparent columnar crystals of Eu-doped GaN were obtained as crusts formed on the Na-Ga melt surface at <I>r</I><SUB>Na</SUB>=0.67 and 650 or 700°C. Under an ultraviolet light, the crusts glowed red. A strong emission peak concerned with the intra-4f transition of Eu<SUP>3+</SUP> from <SUP>5</SUP><I>D</I><SUB>0</SUB> to <SUP>7</SUP><I>F</I><SUB>2</SUB> was observed at 621 nm in the photoluminescence (PL) spectrum. The maximum PL intensity was observed in the sample prepared at <I>r</I><SUB>Na</SUB>=0.67 and 650°C.
粉体および粉末冶金 54(2), 126-129, 2007-02-15
Japan Society of Powder and Powder Metallurgy