Samples of yttrium oxide doped with trivalent europium have been prepared by ceramic techniques, under different synthesis conditions; barium chloride (BaCl2) and sodium tetraborate (Na2B4O7) were tested as flux. The improvement of luminescence properties in dependence on substitution of Eu3+ for Y3+ in the host lattice. under electron and UV excitations is demonstrated. The lattice parameter as a quantitative assessment of activator incorporation degree is proposed. The obtained results are discussed with respect to the employed processing method. (C) 2004 Elsevier Ltd. All rights reserved.