Epitaxial ferroelectric Sr1.9Ca0.1NaNb5O15 (SCNN) thin films have been fabricated successfully by pulsed laser deposition on (100)MgO substrates. Temperature dependency of the vibrational modes of these films was investigated for the first time using Raman scattering technique. For temperatures ranging between 50 degrees C and 450 degrees C, two strong and broad A(1)(TO) phonons around 238 and 608 cm(-1), and one weak B-1(TO) phonon around 142 cm(-1) were observed. Changes in the temperature dependency of the peak position, the full-width at half maximum and integrated intensity of the Raman modes were observed in different temperature ranges. These changes are attributed to the structural phase transitions between 200 degrees C and 325 degrees C for the SCNN films as well as their relaxor properties. (C) 2009 Elsevier B.V. All rights reserved.