Formation of TiO2 and ZrO2 nanotubes using atomic layer deposition with ultraprecise control of the wall thickness

Nanotubes of TiO2 and ZrO2 (see Figure) with diameters of ca. 30-200 nm have been successfully fabricated by atomic layer deposition in a one-step process utilizing nanoporous membranes (commercial polycarbonate filters) as templates. Sub-angstrom wall thickness control and high aspect ratios can be achieved by this method.