Aspect ratio dependence of hysteresis property of high density Co wire array buried in porous alumina template

Long-Range-Ordered Anodic Porous Alumina with Less-Than-30 nm Hole Interval

“…Anodic porous alumina, which is formed by the anodization of Al in an acidic solution, has attracted growing interest as the starting structure of several types of nanodevices because of its unique geometrical structure of uniform-sized holes perpendicular to the surface. [1][2][3] It has been reported that long-range-ordered anodic porous alumina with an ideally ordered hole arrangement could be obtained under appropriate anodization conditions. [4][5][6][7] Such ordered structures are essential for optimizing the performance of the obtained nanodevices.…”

“…The reduction of the hole interval and the hole size of anodic porous alumina while maintaining the long-range ordering of the hole arrangement is very important challenge for expanding the application fields of this material. For example, for the preparation of magnetic recording media, which is a typical application field of anodic porous alumina, by filling the pores with ferromagnetic materials, 2,3) anodic porous alumina with $25 nm hole intervals is expected to achieve a high recording density of more than 1 Tbit/in 2 . However, the preparation of long-range-ordered anodic porous alumina with an ideally ordered hole configuration having hole intervals from 25 to 30 nm has not been reported to date.…”

Fabrication of Ordered Arrays of Anodic Aluminum Oxide Pores with Interpore Distance Smaller than the Pitch of Nano-pits formed by Ion Beam Etching

“…Moreover, the diameter and the depth of the pores are also controllable by growth conditions, such as anodic voltage and duration of anodization, respectively. The regularity of AAO pore arrangement is one of the important issues for applications such as ultra-high density patterned media using magnetic nanowire arrays [10][11][12][13][14][15][16], and the patterning of surfaces for sensors [17][18][19], optically active surfaces [20,21], and for substrates for controlled living cell cultures [22][23][24], and AAO nanopore arrays are considered as the suitable structure for preparation of nanowire and nanodot of various materials [25], such as magnetic and semiconductor materials. However, it is known that the ordered AAO pore arrays can be obtained by several appropriate growth conditions [26], and the inter-pore distances of ordered AAO pore arrays are limited.…”

Electrochemical deposition of Co nanowire arrays into self-organized titania nanotubes

“…So far, Co nanowires have been synthesized by electrodeposition method using anodic porous alumina [10,11] as templates due to easy preparation, and controllable diameter and length of nanowires. Titania nanotubes have also been widely investigated in technological applications, such as photocatalysts, solar cell, gas sensing, self-cleaning, and biosensor application [12][13][14][15].…”