Strain-Dependent Nanowrinkle Confinement of Block Copolymers

Area of Science:

• Materials Science
• Polymer Science
• Nanotechnology

Background:

• Block copolymers (BCPs) are crucial for nanolithography.
• Controlling BCP alignment is challenging, especially on flexible substrates.

Purpose of the Study:

• To develop a soft, templated assembly method for BCPs.
• To achieve programmable alignment of BCPs using polymeric nanowrinkles.
• To explore BCP structural formation mechanisms and control strategies.

Main Methods:

• Utilized polymeric nanowrinkles as a confining scaffold for BCP assembly.
• Manipulated substrate strain to control BCP alignment relative to wrinkle orientation.
• Employed self-consistent field theory (SCFT) modeling to understand BCP formation.
• Investigated various copolymer molecular weights and functional wrinkle surfaces.

Main Results:

• Achieved programmable parallel or perpendicular alignment of poly(styrene)-block-poly(dimethylsiloxane) (PS-b-PDMS) BCPs.
• Demonstrated that wrinkle curvature and surface affinity dictate BCP structural formation.
• Showcased control over BCP alignment on complex wrinkle geometries and functionalized surfaces.

Conclusions:

• Developed an all-soft, templated assembly technique for BCPs.
• Established a method for programmable BCP alignment on flexible 3D architectures.
• This approach offers a promising nanolithography route for next-generation soft electronics.