Evolution of Block Copolymer Lithography to Highly Ordered Square Arrays

Abstract

The manufacture of smaller, faster, more efficient microelectronic components is a major scientific and technological challenge, driven in part by a constant need for smaller lithographically defined features and patterns. Traditional self-assembling approaches based on block copolymer lithography spontaneously yield nanometer-sized hexagonal structures, but these features are not consistent with the industry-standard rectilinear coordinate system. We present a modular and hierarchical self-assembly strategy, combining supramolecular assembly of hydrogen-bonding units with controlled phase separation of diblock copolymers, for the generation of nanoscale square patterns. These square arrays will enable simplified addressability and circuit interconnection in integrated circuit manufacturing and nanotechnology.

Rectangular Symmetry Morphologies in a Topographically Templated Block Copolymer

“…[19,20] The period of the patterns is determined by the BCP chain length, and sub-10-nm-period (sub-5-nm halfpitch) patterns have been reported from low molecular weight BCPs. [8] While a hexagonal lattice of microdomains is readily obtained from a diblock copolymer, obtaining a square symmetry pattern requires 1:1 templating of a diblock copolymer [21] , or use of a triblock terpolymer [22] or a blend of diblock copolymers [23] . We show that by using an array of majority-block-functionalized posts, it is possible to locally control the morphology of a…”

SCFT Simulations of Thin Film Blends of Block Copolymer and Homopolymer Laterally Confined in a Square Well

“…23 A disadvantage of this strategy is that it requires the rather challenging synthesis of ABC triblocks. Tang et al 24 recently demonstrated an alternative route to tetragonal order that involves the use of a binary blend of AB and B'C diblock copolymers in which the B and B' blocks have attractive supramolecular interactions. The self-assembly characteristics of this blend are similar to those of a corresponding ABC triblock system, but its realization requires a less demanding synthesis of two diblock copolymers.…”

Model Transient Networks from Strongly Hydrogen-Bonded Polymers

“…29,30 To broaden the scope and applicability of supramolecular polymer chemistry, many new strongly hydrogen-bonding moieties have been synthesized [31][32][33][34][35][36][37] and incorporated into networkforming materials. [12][13][14][15][38][39][40][41] The strength and specificity of multiple-hydrogen-bonded (MHB) groups vary widely, from weakly complementary pyridine-phenol pairs 42 to extremely strong, self-complementary 6-H-bonded dimers. 31 The 2-ureido-4[1H]-pyrimidinone (UPy) group first reported by Sijbesma et al 12 was developed as a synthetically accessible, exceptionally strong (K dim = 6 Â 10 7 M -1 in CDCl 3 ) quadruple-hydrogenbonded dimer in order to create highly thermally responsive polymeric materials.…”