Growth and characterization of well-aligned rutile TiO2 nanocrystals on sapphire substrates via metal organic vapour deposition

Well-aligned TiO2 nanocrystals (NCs) were prepared by metalorganic chemical vapour deposition on sapphire (SA) (100) and (012) substrates, using Ti[OCH(CH3)2]4 as precursor. The surface morphology, structural and spectroscopic properties of the deposited NCs were characterized using field emission scanning electron microscopy (FESEM), X-ray diffractometry (XRD) and Raman spectroscopy (RS). FESEM micrographs show that the NCs on SA(100) are vertically aligned. XRD determines the preferable orientations of the as-deposited NCs. RS confirms rutile phase of the NCs. The roles of substrate orientations for the formation of different textures of TiO2 NCs are discussed.