LiTaO(3) thin films were deposited by radio-frequency magnetron sputtering with a Li enriched target composed of Li(2)O(2)/Ta(2)O(5) (55:45 at%). Morphology, crystallinity, dielectric and pyrolectric properties of thin films of LiTaO(3) are studied according to the temperature of deposition and the nature of the back electrode (Ru/RuO(2) and RuO(2)). In order to develop thermal microsensors; containing pyrolectric thin layers deposited on membranes of SiN(x) ensuring the thermal isolation of the device, the final aim is to improve the pyroelectric coefficient for infrared pyroelectric detectors applications. The best pyroelectric coefficient of LiTaO(3) thin films (400 nm), obtained for a growth temperature of 620 degrees C and a pressure of 0.67 Pa, is equal to 40 mu C/m(2) K. (C) 2008 Elsevier B.V. All rights reserved.