Flat and Roll-type Translucent Anodic Porous Alumina Molds Anodized in Oxalic Acid for UV Nanoimprint Lithography

Overview

Journal RSC Adv

Publisher Royal Society of Chemistry

Specialty Chemistry

Date 2023 Nov 15

PMID 37964907

Authors

Takashi Yanagishita

Naoko Kumagai

Hideki Masuda

Affiliations

Soon will be listed here.

Abstract

There is much interest in UV nanoimprinting as a fabrication method for various functional devices because of its suitability for efficient fine patterning. To form patterns on opaque substrates by UV nanoimprinting, it is essential to use molds through which UV light can pass. In this study, translucent anodic porous alumina (APA) molds for UV nanoimprinting were fabricated by the anodization of an Al substrate. To fabricate a translucent APA mold, an ordered APA film used as a mold for UV nanoimprinting was formed on the surface side of the Al substrate, and then anodization was continued from the back surface of the Al substrate to increase its transparency in the UV spectral range. A gradient change of Al thickness is necessary for the production of a large-area translucent mold, since it lowers the thickness of opaque defects remaining in the mold. The resulting translucent mold was effective for UV nanoimprinting to prepare ordered polymer nanopillar arrays on the surfaces of opaque substrates because the transmittance of the resulting translucent APA mold was 40% at a wavelength of 365 nm, which was confirmed to be sufficiently translucent to polymerize the photocurable monomer used in this study. In addition, it was possible to fabricate roll-type translucent APA molds by using Al pipes as a starting material. A seamless ordered nanopillar array can be effectively formed on a substrate by continuous UV nanoimprinting using the resulting roll-type translucent APA molds. Ordered nanopillar arrays formed on opaque substrates by UV nanoimprinting using translucent APA molds have various potential applications, such as those for forming antireflective and water-repellent surfaces.

References

Santos A, Law C, Chin Lei D, Pereira T, Losic D . Fine tuning of optical signals in nanoporous anodic alumina photonic crystals by apodized sinusoidal pulse anodisation. Nanoscale. 2016; 8(43):18360-18375. DOI: 10.1039/c6nr06796d. View

Sun J, Wang X, Wu J, Jiang C, Shen J, Cooper M . Biomimetic Moth-eye Nanofabrication: Enhanced Antireflection with Superior Self-cleaning Characteristic. Sci Rep. 2018; 8(1):5438. PMC: 5883013. DOI: 10.1038/s41598-018-23771-y. View

Szwachta G, Bialek E, Wlodarski M, Norek M . Structural stability and optical properties of 1D photonic crystals based on porous anodic alumina after annealing at different temperatures. Nanotechnology. 2022; 33(45). DOI: 10.1088/1361-6528/ac83ca. View

Traub M, Longsine W, Truskett V . Advances in Nanoimprint Lithography. Annu Rev Chem Biomol Eng. 2016; 7:583-604. DOI: 10.1146/annurev-chembioeng-080615-034635. View

Liu S, Tian J, Zhang W . Fabrication and application of nanoporous anodic aluminum oxide: a review. Nanotechnology. 2021; 32(22). DOI: 10.1088/1361-6528/abe25f. View

Li Y, Chen Y, Qiu M, Yu H, Zhang X, Sun X . Preparation of Aluminum Nanomesh Thin Films from an Anodic Aluminum Oxide Template as Transparent Conductive Electrodes. Sci Rep. 2016; 6:20114. PMC: 4735723. DOI: 10.1038/srep20114. View

Cattoni A, Ghenuche P, Haghiri-Gosnet A, Decanini D, Chen J, Pelouard J . λ³/1000 plasmonic nanocavities for biosensing fabricated by soft UV nanoimprint lithography. Nano Lett. 2011; 11(9):3557-63. DOI: 10.1021/nl201004c. View

Devarakonda S, Ganapathysubramanian B, Shrotriya P . Impedance-Based Nanoporous Anodized Alumina/ITO Platforms for Label-Free Biosensors. ACS Appl Mater Interfaces. 2021; 14(1):150-158. DOI: 10.1021/acsami.1c17243. View

Law C, Lim S, Liu L, Abell A, Marsal L, Santos A . Realization of high-quality optical nanoporous gradient-index filters by optimal combination of anodization conditions. Nanoscale. 2020; 12(17):9404-9415. DOI: 10.1039/c9nr10526c. View

10.

Arbabi A, Horie Y, Ball A, Bagheri M, Faraon A . Subwavelength-thick lenses with high numerical apertures and large efficiency based on high-contrast transmitarrays. Nat Commun. 2015; 6:7069. DOI: 10.1038/ncomms8069. View

11.

Masuda H, Fukuda K . Ordered metal nanohole arrays made by a two-step replication of honeycomb structures of anodic alumina. Science. 1995; 268(5216):1466-8. DOI: 10.1126/science.268.5216.1466. View

12.

Yanagishita T, Yoshida M, Masuda H . Renewable Superhydrophobic Surfaces Prepared by Nanoimprinting Using Anodic Porous Alumina Molds. Langmuir. 2021; 37(35):10573-10578. DOI: 10.1021/acs.langmuir.1c01805. View

13.

Jin S, Wang Y, Motlag M, Gao S, Xu J, Nian Q . Large-Area Direct Laser-Shock Imprinting of a 3D Biomimic Hierarchical Metal Surface for Triboelectric Nanogenerators. Adv Mater. 2018; 30(11). DOI: 10.1002/adma.201705840. View

14.

van Dommelen R, Fanzio P, Sasso L . Surface self-assembly of colloidal crystals for micro- and nano-patterning. Adv Colloid Interface Sci. 2017; 251:97-114. DOI: 10.1016/j.cis.2017.10.007. View

15.

Truskett V, Watts M . Trends in imprint lithography for biological applications. Trends Biotechnol. 2006; 24(7):312-7. DOI: 10.1016/j.tibtech.2006.05.005. View

16.

Acosta L, Law C, Lim S, Abell A, Marsal L, Santos A . Role of Spectral Resonance Features and Surface Chemistry in the Optical Sensitivity of Light-Confining Nanoporous Photonic Crystals. ACS Appl Mater Interfaces. 2021; 13(12):14394-14406. DOI: 10.1021/acsami.1c00914. View

17.

Kumeria T, Rahman M, Santos A, Ferre-Borrull J, Marsal L, Losic D . Structural and optical nanoengineering of nanoporous anodic alumina rugate filters for real-time and label-free biosensing applications. Anal Chem. 2014; 86(3):1837-44. DOI: 10.1021/ac500069f. View

18.

Yanagishita T, Murakoshi K, Kondo T, Masuda H . Preparation of superhydrophobic surfaces with micro/nano alumina molds. RSC Adv. 2022; 8(64):36697-36704. PMC: 9088829. DOI: 10.1039/c8ra07497f. View

19.

Yoon G, Kim K, Huh D, Lee H, Rho J . Single-step manufacturing of hierarchical dielectric metalens in the visible. Nat Commun. 2020; 11(1):2268. PMC: 7211027. DOI: 10.1038/s41467-020-16136-5. View