Properties of electron trapping materials influenced by the synthesizing conditions

Stoichiometry of the major activators in electron trapping materials (ETM), prepared by sulfurizing flux method (SFM) and the rare earth direct doped technique, is measured by means of the induction coupled plasma mass spectrum (ICP-MS). It is shown that the rare earth direct doped technique is better than SFM. Influenced by the synthesizing conditions, the variation of valence state of the main activators, such as Eu in Cas: Eu, Sm, is discussed by analyzing the charge trapping mechanism and spectra of ETM.