The FeSix thin films with the flatness to an atomic scale for mechanical and optical applications can be grown by a facing target sputtering method. Optical properties indicate the films contain nano-crystalline FeSi2. The nano-indentation hardness of 10 GPa was obtained. An interesting point is that Young's modulus is larger than that of the carbon-based materials with the same hardness. This means that the FeSix is more elastic, which could be characteristic of the chemical bonding of the FeSi2 with the large contribution of cl-electrons. Furthermore, results of the Hall measurement at room temperature shows that the films have p-type conductivity, a carrier concentration of p = 2.49 x 10(20) cm(-3) and a Hall mobility of mu = 6.42 cm(2) V-1 s(-1). (c) 2007 Elsevier B.V. All rights reserved.