Fabrication of 5 Tdot/in.2 bit patterned media with servo pattern using directed self-assembly

Abstract

The fabrication of an etching template for 5 Td/in.2 bit patterned media using a self-organization material, namely, poly(styrene)-poly(dimethylsiloxane) (PS-PDMS), was investigated. The molecular weight of the PS-PDMS for forming the areal density of 5 Td/in.2 dot pattern was estimated from the polymerization index related to the Flory–Huggins interaction parameter. Annealing was carried out to obtain a fine-order dot pattern. PS-PDMS films were subjected to thermal treatment or solvent annealing. The ordering of the dot array in these films was evaluated by using Voronoi diagrams. The results indicate that the film annealed in N-methylpyrrolidone (NMP) vapor showed finer ordering than did the thermally treated film. This seemed to be attributable to the high solubility parameter of NMP. The soaking of NMP into the PS phase slightly shifted the phase separation energy of the polymer matrix. The lattice spacing of the obtained hexagonal pattern was 11 nm. By using low-molecular-weight PS-PDMS with solvent annealing, a dot-array template for 5 Td/in.2 bit patterned media was formed.

Directed Self-Assembly and Pattern Transfer of Five Nanometer Block Copolymer Lamellae

“…Numerous DSA schemes that use lithography to pattern chemical , or topographical , guide features have been reported. By carefully tailoring the dimensions and the surface chemistry of the guiding patterns, BCP films can be induced to produce many device-relevant features − with low pattern registration error. , In addition, DSA processes can repair defects and misplaced features in the guide pattern lithography . Typically, guiding features for DSA are designed such that they have little or no topography (chemoepitaxy). ,− However, so-called hybrid chemo-/grapho- epitaxy DSA schemes − purposely incorporate some topography in the guiding features to provide an additional guiding force for alignment.…”

Influence of spin casting solvent on the self‐assembly of silicon‐containing block copolymer thin films via high temperature thermal treatment

“…Therefore, the annealing process usually needs hours to allow the self‐assembly (SA) of the DBCs by low temperature thermal treatment in conventional furnaces. The extremely slow SA process kinetics are not compatible with the stringent requirements of standard industrial processing 14,15 . In order to overcome this limitation, high temperature thermal treatments could represent a simple, convenient and highly effective solution to speed up the SA kinetics of PDMS‐containing DBCs 6 .…”

Directed Self-Assembly on Photo-Crosslinked Polystyrene Sub-Layers: Nanopattern Uniformity and Orientation

“…The self-assembly of block copolymers (BCPs) has, over the past decade, become a powerful technique for fabricating functional templates and scaffolds for advanced devices such as bit-patterned media [ 1 ], memory devices [ 2 ], nanowire-based transistors [ 3 , 4 ], arrays of quantum dots or metallic nanoparticles [ 5 , 6 ], and ultrafiltration membranes [ 7 ]. This has been made possible by the intrinsic ability of BCPs to form highly ordered polymeric structures with periodicities on a nanometer scale.…”