Electromagnetic (EM) metasurface with wireless signal control function fabricated by 3D printing

Area of Science:

• Materials Science
• Electrical Engineering
• Additive Manufacturing

Background:

• Traditional planar frequency selective surfaces (2DFSS) exhibit performance limitations with varying incident angles and polarization.
• Existing fabrication methods for volumetric electronics often involve complex processes or particle-based conductive inks.
• There is a need for advanced manufacturing techniques to create high-performance, spatially integrated electronic components.

Purpose of the Study:

• To develop a novel 3D printing technology for fabricating high-performance volumetric electronic circuits.
• To introduce a particle-free conductive system for creating localized, controllable conductive coatings.
• To extend frequency selective surfaces (FSS) from planar to volumetric dimensions (3DFSS) for improved electromagnetic wave manipulation.

Main Methods:

• A particle-free conductive system utilizing a nontoxic reductant-functionalized polymer coating was developed.
• In-situ reduction of silver onto custom-designed substrates was employed to form highly conductive and controllable coatings.
• The fabrication of 3D frequency selective surfaces (3DFSS) was achieved by leveraging the developed conductive system.
• Equivalent circuit models (ECM) were used to provide design guidelines for transitioning 3DFSS to filter responses.

Main Results:

• The proposed 3DFSS demonstrated significantly stable filtering performance across various incident angles and polarization modes.
• The fabricated FSS achieved a wide operational bandwidth of 4.4-7.8 GHz (54.8% fractional bandwidth) with a reflection coefficient below -10 dB.
• The designed array FSS exhibited excellent structural compactness and mechanical robustness.
• The technology enables electromagnetic signal modulation across scales, addressing compatibility and signal quality issues.

Conclusions:

• The novel 3D printing technology successfully enables the fabrication of high-performance volumetric electronic circuits.
• The particle-free conductive system and 3DFSS approach offer superior electromagnetic filtering characteristics compared to traditional 2DFSS.
• The developed 3DFSS technology is suitable for seamless integration with building materials and offers solutions for electromagnetic compatibility in miniaturized communication systems.