Transparent thin films of (Eu,Y1-x)(2)SiO5 and (Eu,Y1-x)(2)Si2O7 (x = 0.005 similar to 0.05) have been prepared using a metallorganic decomposition sol-gel process. A strong room temperature red emission with predominant wavelength at 614 nm, corresponding to the D-5(o) --> F-7(2) intra-4f(n) electric transition of Eu3+, has been observed as a function of the annealing temperature. Correlations were observed between optical properties and film structures. As a consequence, a great change in luminescence and CIE coordinates of Eu3--doped Y2SiO5 at high temperature around 1050 degreesC was attributed to phase transformation of nanocrystalline films. Upon exposure to the UV source, these thin films have shown bright red-phosphorescent color with excellent color saturation. (C) 2002 Published by Elsevier Science B.V.