Emergent Soft Lithographic Tools for the Fabrication of Functional Polymeric Microstructures

Area of Science:

• Materials Science
• Nanotechnology
• Chemical Engineering

Background:

• Polymeric microstructures (PMs) are crucial for technologies like sensing, energy storage, and soft robotics.
• Traditional fabrication methods include photolithography, 3D printing, and micromilling.
• Soft lithography, using elastomeric masters, offers unique capabilities for PM fabrication.

Purpose of the Study:

• To review emergent soft lithographic methods.
• To explore novel elastomeric master fabrication techniques.
• To highlight the impact of these methods on PM applications.

Main Methods:

• Utilizing self-forming, dynamic, 3D, or sacrificial elastomeric masters.
• Employing techniques such as replica molding and microcontact printing with advanced masters.
• Fabricating PMs on non-planar substrates using cost-effective equipment.

Main Results:

• Enabled fabrication of PMs with hierarchical microstructures, overhanging features, and 3D architectures.
• Introduced new master types: self-assembled liquid droplets, microscale balloons, natural material templates, and hierarchically microstructured surfaces.
• Expanded the scope of PMs achievable through soft lithography.

Conclusions:

• Next-generation soft lithography with advanced masters significantly broadens the possibilities for PM fabrication.
• These methods redefine existing technological communities and create new ones.
• The reviewed techniques promise to impact a wide range of applications in sensing, energy, and robotics.