Spatially Controlled Fabrication of Nanoporous Block Copolymers

Abstract

A light-driven process for fabrication of spatially controlled nanoporous polymer films was demonstrated with a new diblock copolymer/small molecule additive system. Poly(Rmethylstyrene-b-4-hydroxystyrene) was designed and synthesized with one block functioning as a high-resolution negative-tone photoresist and the second block being selectively removable. With a straightforward spin-coating process, a perpendicular cylindrical orientation of the removable block R-methylstyrene microdomain was induced over a wide range of film thicknesses on different substrates. Uniform nanometer-sized pores in submicron-sized photopatterns can be generated by merger of "top down" photolithographic imaging with a subsequent selective removal of a "bottom up" self-assembled nanostructure.

Fabrication of Hierarchically Ordered Hybrid Structures over Multiple Length Scales via Direct Etching of Self-Organized Polyhedral Oligomeric Silsesquioxane (POSS) Functionalized Block Copolymer Films

“…On the other hand, instead of these approaches, combinations of various kind of molecular self-organization and facile direct lithographic techniques are of particular recent interests. [12][13][14] The advantage of using the molecular self-organization is that one can directly produce ordered two-or three-dimensional hierarchically structures and tailored surfaces by a single step.…”

20nm Pitch Directed Block Copolymer Assembly Using Solvent Annealing for Bit Patterned Media

“…[8] This may be advantageous -it could offer a method for selectively removing that block for pattern transfer. [13] We show here that a single solvent may be used to form two different ordering patterns by altering the anneal time, and thus the degree of swelling. PαMS-b-P4VP films on unpatterned PS brush on Si form parallel cylinder morphologies when annealed in THF for moderate times (in this case, 6 hours).…”

Top-down Meets Bottom up: Block Copolymers with Photoreactive Segments

“…[9,10] Depending on selection of solvent vapor microstructure was reversible up to the point negative tone patterning was carried out. [11] In another system, as yet unpublished, the (PHEMA-b-PMMA) system formed cylinders of the PMMA block in a matrix of PHEMA.…”