1996 年 104 巻 1216 号 p. 1129-1132
Red light emitting phosphors (Y, Eu, Ln)2O2S were crystallized in (Li2CO3+S) fluxes containing various rare earth ions such as La3+, Nd3+, Gd3+, Yb3+ and Lu3+. According to the SEM observations, the grain size of (Y, Eu)2O2S was decreased by adding La3+, Nd3+ or Gd3+ ions, but increased by adding Yb3+ or Lu3+ ions. Such a profile was closely related to the changes of the unit cell parameters of (Y, Eu, Ln)2O2S. Addition of La3+ ions has given little effect on the luminescent properties and the formation reaction mechanism of (Y, Eu)2O2S. Furthermore, the minimum grain size of (Y, Eu)2O2S phosphor was obtained at 3mol% of La3+ doping. The flux growth mechanism was disscussed in the formation process of oxysulfides.