Fabrication of Ordered Arrays of Nanodots Using Porous Alumina Thin Film Templates

Current Applied Physics, 2007

Thin nanodotstructured metal films and heterostructured nanodot arrays (metal nanodot arrays/Si) with a high density and uniform distribution for various kinds of metals (Au, Al, Ag, Pb, Cu, Sn, and Zn) were fabricated by thermal vacuum evaporation using an anodic porous alumina membrane as a template. However, for such metals as Sn, Zn, and Pb with relatively lower melting point as compared with Al it was found that heterostructured nanodot arrays were not formed by a single stage of evaporation. For these metals, we developed a new method termed ''two step evaporation method''. The size and the arrays of dots were depended on the pore structure in the anodic porous alumina template. The technique demonstrated in this report is simple and suitable for the preparation of nanodot arrays in the large area for materials which could be vacuum evaporated.

Small, 2010

Using ultrathin alumina membranes (UTAMs) as evaporation or etching masks large-scale ordered arrays of surface nanostructures can be synthesized on substrates. However, it is a challenge for this technique to synthesize quantum-sized surface structures. Here an innovative approach to prepare UTAMs with regularly arrayed pores in the quantum size range is reported. This new approach is based on a well-controlled pore-opening process and a modulated anodization process. Using UTAMs with quantum-sized pores for the surface patterning process, ordered arrays of quantum dots are synthesized on silicon substrates. This is the first time in realizing large-scale regularly arrayed surface structures in the quantum size range using the UTAM technique, which is an important breakthrough in the field of surface nanopatterning.

The authors demonstrate a nanofabrication method utilizing nanoporous alumina templates which involves directed three dimensional assembly of nanoparticles inside the pores by means of an electrophoretic technique. In their demonstration, they have assembled polystyrene nanobeads with diameter of 50 nm inside nanopore arrays of height of 250 nm and diameter of 80 nm. Such a technique is particularly useful for large-scale, rapid assembly of nanoelements for potential device applications. ©2007 American Institute of Physics http:// http://link.aip.org/link/?APPLAB/90/163119/1

physica status solidi (RRL) – Rapid Research Letters, 2008

One-dimensional structures have attracted a great interest in the last two decades in broad areas of nanotechnology, such as electronics, sensing, and information technology. For future applications, one of the biggest challenges is their controlled organization on a substrate. An elegant approach is template growth, in which a preexisting structure defines the nanowires geometry. Porous anodic aluminum oxide (AAO) film has attracted much interest due to the high aspect ratio, high degree of ordering, high pore density, uniformity and low cost synthesis . AAO templates are commonly obtained with the pores oriented vertically on a substrate . Unfortunately, this method offers some difficulties for their compatibility with the mainstream Si planar technology. However, a significant advance has been achieved in the last years towards the fabrication of horizontal AAO templates on a chip .

Journal of Applied Physics, 2010

2003

Starting from two-step anodizing recipes available in the literature, we fabricated self-supporting ordered ion-implantation masks that are several mm2 in area and approximately 2 μm thick. SEM micrographs reveal self-organized structures with straight open pores, 50–150 nm in diameter, extending completely through the mask. As reported previously, the pore diameter and spacing depend critically upon the anodization parameters, eg type of acid and its molality, the applied voltage and the solution temperature.

physica status solidi (a), 2009

Korean Journal of Chemical Engineering, 2008

A novel method for the fabrication of highly ordered nanopore arrays with very small diameter of 14 nm was demonstrated by using low-temperature anodization. Two-step anodization was carried out at 25 V, sulfuric acid concentration of 0.3 M, and electrolyte temperature of −15 o C. After anodization, a regular pore array with mean diameter of 14 nm and interpore distance of 65 nm was formed. The pore diameter and regular arrangement were confirmed by scanning electron microscopy (SEM) and fast Fourier transformation (FFT), respectively. The present results strongly suggest that the diameter of pores in a highly ordered alumina template can be reduced by lowering the anodization temperature.

Small, 2008

2015

Porous anodic aluminum oxide film is a versatile template for the fabrication of nanomaterials. Porous alumina can be fabricated electrochemically through anodic oxidation of aluminum by self-organization method yielding highly ordered arrays of nanoholes. Various techniques such as chemical vapor deposition, electrodeposition, spin coating, dip coating, physical vapor deposition are elaborated for the fabrication of nanomaterials using porous anodic alumina as template.