Directed self-assembly of a two-state block copolymer system.

Area of Science:

• Materials Science
• Polymer Chemistry
• Nanotechnology

Background:

• Block copolymers self-assemble into complex nanostructures.
• Controlling these structures at the nanoscale is crucial for advanced materials.
• Understanding confined self-assembly is key to directed fabrication.

Purpose of the Study:

• To form and control ladder-shaped block copolymer structures within square confinement.
• To investigate the properties of the resulting binary states.
• To demonstrate methods for manipulating and scaling these binary states.

Main Methods:

• Fabrication of ladder-shaped block copolymer structures inside square confinement.
• Utilizing self-consistent field theory (SCFT) simulations.
• Modifying confinement geometry, wall openings, and lithographic guiding patterns.

Main Results:

• Successfully formed parallel bars, bends, and T-junctions in block copolymer structures.
• Defined binary states based on two degenerate alignment orientations.
• Demonstrated control over binary states via confinement modifications and guiding patterns.
• SCFT simulations validated experimental findings, showing templating effects.

Conclusions:

• Ladder-shaped block copolymer structures can be precisely templated within confined geometries.
• The binary states of these structures are controllable through external stimuli.
• This work enables the scaling of single binary states into larger, individually controllable arrays for potential applications.