We fabricated of nanotubular structures of TiO2 and ZrO2 using the gas-phase fabrication method atomic layer deposition (ALD) with nanoporous structure of polycarbonate (PC) templates. Contact printed alkylsiloxane monolayers on both sides of PCs were prepared for one-step process of the freestanding oxide nanotubes. 30 ~ 200 nm of diameter TiO2 and ZrO2 nanotubes were successfully fabricated by ALD at 140 _C and subsequent chemical etching of the PC. Prepared oxide nanotubes are characterized by high-resolution TEM, field emission SEM, and atomic force microscopy (AFM). Prepared TiO2 nanotubes are mostly amorphous, while the ZrO2 nanotubes contained more nanocrystallites. Very high aspect ratio of 200:1 was achieved in both oxide nanotubes. Growth rates of the wall thickness in oxides nanotubes were 0.5 and 0.6 Å/cycles for 200 and 50 nm pore sizes of PC templates, respectively, showing ultra-precise control of the wall thickness, so as to inner diameter of the tubes. Further we developed ALD processes for Cu layer and coaxial nanocables of TiO2/Cu and/or ZrO2/Cu were successfully fabricated with the same method as described above. Combination of the ultra-precise wall thickness control of oxide nanotube with high-aspect ratio filled Cu layer provides us a possible quantum coaxial cable in the nanoelectronic applications.
Journal: TechConnect Briefs
Volume: 2, Technical Proceedings of the 2005 NSTI Nanotechnology Conference and Trade Show, Volume 2
Published: May 8, 2005
Pages: 638 - 641
Industry sector: Advanced Materials & Manufacturing
Topics: Nanoparticle Synthesis & Applications