Limits...
Fabrication of ordered nanoporous anodic alumina prepatterned by mold-assisted chemical etching.

Lai KL, Hon MH, Leu IC - Nanoscale Res Lett (2011)

Bottom Line: In this article, a simple and cost-effective method to create patterned nanoindentations on Al surface via mold-assisted chemical etching process is demonstrated.During subsequent anodization, it was possible to obtain the ordered nanopore arrays with 277 nm pitch that were guided by the prepatterned etch pits.The prepatterned etch pits obtained can guide the growth of AAO nanopores during anodization and facilitate the preparation of ordered nanopore arrays.

View Article: PubMed Central - HTML - PubMed

Affiliation: Department of Materials Science, National University of Tainan, Tainan 700, Taiwan. icleu@mail.mse.ncku.edu.tw.

ABSTRACT
In this article, a simple and cost-effective method to create patterned nanoindentations on Al surface via mold-assisted chemical etching process is demonstrated. This report shows the reaction-diffusion method which formed nanoscale shallow etch pits by the absorption/liberation behaviors of chemical etchant in poly(dimethylsiloxane) stamp. During subsequent anodization, it was possible to obtain the ordered nanopore arrays with 277 nm pitch that were guided by the prepatterned etch pits. The prepatterned etch pits obtained can guide the growth of AAO nanopores during anodization and facilitate the preparation of ordered nanopore arrays.

No MeSH data available.


Related in: MedlinePlus

AFM and SEM images of Al prepattern and AAO (a, b) Al prepattern featuring a second grating on a primary structure with ~85° rotation and pitch of 277 nm. (c, d) prepattern-induced regular AAO array. Anodization conducted in 0.3 M H3PO4 at 110 V and 5°C.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC3211208&req=5

Figure 5: AFM and SEM images of Al prepattern and AAO (a, b) Al prepattern featuring a second grating on a primary structure with ~85° rotation and pitch of 277 nm. (c, d) prepattern-induced regular AAO array. Anodization conducted in 0.3 M H3PO4 at 110 V and 5°C.

Mentions: Furthermore, the two-step imprinting was used to fabricate multiple patterns from a single master. The two-step imprinting can be used to selectively etch Al at established primary structure because the etchant only acts at the contact site between the mold and substrate [18]. After the first mold-assisted etching, a second etching step was performed using the same grating rotated by approximately 85° around the axis perpendicular to the surface to discriminate this multiple case from one-step imprinting method. A parallelogram profile of etched pit arrays was obtained, as illustrated in Figure 5a,b. From the AFM images, the intersects of grating pattern show shallow indent arrays which resemble point-like depressions [5,12] and have just several nanometers in depth relative to the local surface around them. In addition, the double-etching sites serve as the nucleation sites, and the ordered AAO growth can be maintained as shown in Figure 5c,d. A single pore just appears on double-etching site and the notches of multiple etching remain on the AAO surface and parallelogram (i.e., non-right angle) patterns of pore arrays are obviously different from the directly imprinted 2D square prepatterns (Figure 4b). All of these experimental findings suggest that this mold-assisted etching method is industrially applicable to a large-scale production of nanopatterning and has the potential of achieving the aim of fabricating nanostructured functional AAO with required design geometry.


Fabrication of ordered nanoporous anodic alumina prepatterned by mold-assisted chemical etching.

Lai KL, Hon MH, Leu IC - Nanoscale Res Lett (2011)

AFM and SEM images of Al prepattern and AAO (a, b) Al prepattern featuring a second grating on a primary structure with ~85° rotation and pitch of 277 nm. (c, d) prepattern-induced regular AAO array. Anodization conducted in 0.3 M H3PO4 at 110 V and 5°C.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC3211208&req=5

Figure 5: AFM and SEM images of Al prepattern and AAO (a, b) Al prepattern featuring a second grating on a primary structure with ~85° rotation and pitch of 277 nm. (c, d) prepattern-induced regular AAO array. Anodization conducted in 0.3 M H3PO4 at 110 V and 5°C.
Mentions: Furthermore, the two-step imprinting was used to fabricate multiple patterns from a single master. The two-step imprinting can be used to selectively etch Al at established primary structure because the etchant only acts at the contact site between the mold and substrate [18]. After the first mold-assisted etching, a second etching step was performed using the same grating rotated by approximately 85° around the axis perpendicular to the surface to discriminate this multiple case from one-step imprinting method. A parallelogram profile of etched pit arrays was obtained, as illustrated in Figure 5a,b. From the AFM images, the intersects of grating pattern show shallow indent arrays which resemble point-like depressions [5,12] and have just several nanometers in depth relative to the local surface around them. In addition, the double-etching sites serve as the nucleation sites, and the ordered AAO growth can be maintained as shown in Figure 5c,d. A single pore just appears on double-etching site and the notches of multiple etching remain on the AAO surface and parallelogram (i.e., non-right angle) patterns of pore arrays are obviously different from the directly imprinted 2D square prepatterns (Figure 4b). All of these experimental findings suggest that this mold-assisted etching method is industrially applicable to a large-scale production of nanopatterning and has the potential of achieving the aim of fabricating nanostructured functional AAO with required design geometry.

Bottom Line: In this article, a simple and cost-effective method to create patterned nanoindentations on Al surface via mold-assisted chemical etching process is demonstrated.During subsequent anodization, it was possible to obtain the ordered nanopore arrays with 277 nm pitch that were guided by the prepatterned etch pits.The prepatterned etch pits obtained can guide the growth of AAO nanopores during anodization and facilitate the preparation of ordered nanopore arrays.

View Article: PubMed Central - HTML - PubMed

Affiliation: Department of Materials Science, National University of Tainan, Tainan 700, Taiwan. icleu@mail.mse.ncku.edu.tw.

ABSTRACT
In this article, a simple and cost-effective method to create patterned nanoindentations on Al surface via mold-assisted chemical etching process is demonstrated. This report shows the reaction-diffusion method which formed nanoscale shallow etch pits by the absorption/liberation behaviors of chemical etchant in poly(dimethylsiloxane) stamp. During subsequent anodization, it was possible to obtain the ordered nanopore arrays with 277 nm pitch that were guided by the prepatterned etch pits. The prepatterned etch pits obtained can guide the growth of AAO nanopores during anodization and facilitate the preparation of ordered nanopore arrays.

No MeSH data available.


Related in: MedlinePlus