Growth and characterization of TiO2 nanotubes from sputtered Ti film on Si substrate
1 Electrical and Computer Engineering Department, University of Utah, 50 South Central Campus Dr, MEB 3280, Salt Lake City, UT, 84112, USA
2 Metallurgical Engineering Department, University of Utah, 135 South 1460 East, WBB 00412, Salt Lake City, UT, 84112, USA
3 Chemical Engineering Department, University of Utah, 50 South Central Campus Dr, MEB 3290, Salt Lake City, UT, 84112, USA
Nanoscale Research Letters 2012, 7:388 doi:10.1186/1556-276X-7-388Published: 12 July 2012
In this paper, we present the synthesis of self-organized TiO2 nanotube arrays formed by anodization of thin Ti film deposited on Si wafers by direct current (D.C.) sputtering. Organic electrolyte was used to demonstrate the growth of stable nanotubes at room temperature with voltages varying from 10 to 60 V (D.C.). The tubes were about 1.4 times longer than the thickness of the sputtered Ti film, showing little undesired dissolution of the metal in the electrolyte during anodization. By varying the thickness of the deposited Ti film, the length of the nanotubes could be controlled precisely irrespective of longer anodization time and/or anodization voltage. Scanning electron microscopy, atomic force microscopy, diffuse-reflectance UV–vis spectroscopy, and X-ray diffraction were used to characterize the thin film nanotubes. The tubes exhibited good adhesion to the wafer and did not peel off after annealing in air at 350 °C to form anatase TiO2. With TiO2 nanotubes on planar/stable Si substrates, one can envision their integration with the current micro-fabrication technique large-scale fabrication of TiO2 nanotube-based devices.