Fabrication and characterization of bit-patterned media beyond 1.5 Tbit/in²

Abstract

We fabricated bit-patterned media (BPM) at densities as high as 3.3 Tbit/in(2) using a process consisting of high-resolution electron-beam lithography followed directly by magnetic film deposition. By avoiding pattern transfer processes such as etching and liftoff that inherently reduce pattern fidelity, the resolution of the final pattern was kept close to that of the lithographic step. Magnetic force microscopy (MFM) showed magnetic isolation of the patterned bits at 1.9 Tbit/in(2), which was close to the resolution limit of the MFM. The method presented will enable studies on magnetic bits packed at ultra-high densities, and can be combined with other scalable patterning methods such as templated self-assembly and nanoimprint lithography for high-volume manufacturing.

Perpendicular magnetic anisotropy and the magnetization process in CoFeB/Pd multilayer films

“…Moderately high M s in some samples would be an interesting aspect for perpendicular magnetic recording technology. 43 9…”

High resolution fabrication of nanostructures using controlled proximity nanostencil lithography

“…Nanogap structures are important in a broad range of devices, including surface enhanced Raman spectroscopy (SERS) 10 , single molecule fluorescence sensing 11,12 , transverse electrodes for nanopore sensing 13 , spin 14 and ultrafast 15 transistors, molecular electronics 16,17 , magnetic tunneling junctions 18 , and nanomagnetics 19 . In many of these applications, device performance depends critically on both the gap size as well as the feature dimensions 20 , and is sensitive to geometric and surface imperfections that often lead to a significant deterioration in performance 21 .…”

Development of Functional Metallic Glassy Materials by FIB and Nanoimprint Technologies

“…At an areal recording density of 2 Tbit/in 2 , the dot pitch (L p ) of the magnetic bits is 18 nm. In order to produce bit patterned media, the ultrafine dot array is determined by nanopatterning techniques such as self-assembly with a block copolymer [46], electron beam (EB) lithography [47,48], extreme ultra violet lithography, [49], and nanoimprint lithography [50]. Nanoimprinting is also a promising fabrication method for high efficiency and low-cost mass production of bit patterned media [51].…”