Synthesis of titania or titanium dioxide (TiO 2) is attracted to energy and environmental applications. Here, the growth of nanostructure TiO 2 nanowires on Si (100) substrates by using the two-step method. Different seed layers of TiO 2 were deposited by spin coating and annealing, followed by the growth of TiO 2 nanowires by using the hydrothermal method. The sol-gel technique was used in preparing the TiO 2 solution for the thin film deposition purpose. Acetic acid, hydrochloric acid and tris (2-aminoethyl) amine were used as a stabilizer to synthesize three different TiO 2 seed layers. The aim of this study was to understand the role of polycrystalline size on thin film towards the diameter of nanowires grown as a sensing area in Surface Acoustic Wave (SAW) Biosensor. The morphology and structure of the thin film and TiO 2 nanowires were characterized using X-Ray diffraction (XRD), scanning electron microscope
(SEM), field emission scanning electron microscope (FESEM) and atomic force microscopy (AFM).