Liquid Metal Grid Patterned Thin Film Devices Toward Absorption-Dominant and Strain-Tunable Electromagnetic...

Area of Science:

• Materials Science
• Electrical Engineering
• Nanotechnology

Background:

• Increasing demand for high-performance, deformable electromagnetic interference (EMI) shielding in soft and wearable electronics.
• Traditional reflective shielding materials lack deformability and can cause secondary electromagnetic pollution.

Purpose of the Study:

• To present soft and stretchable EMI shielding thin-film devices with absorption-dominant shielding behavior.
• To overcome the limitations of rigid, reflective EMI shielding materials.

Main Methods:

• Fabrication of devices using a liquid metal (LM) layer and an LM grid-patterned layer separated by an elastomeric film.
• Utilizing aerosol deposition for superior adhesion of LM on elastomer.
• Characterization of EMI shielding effectiveness (SE) and reflectance under various strain conditions.

Main Results:

• Achieved high total EMI shielding effectiveness (SE_T) up to 75 dB with low reflectance (SE_R of 1.5 dB at resonant frequency).
• Demonstrated absorption-dominant EMI shielding attributed to multiple internal reflections within LM grid architectures.
• Exhibited excellent stretchability, enabling tunable shielding by adjusting grid spacing under strain (resonant frequency shift from 81.3 to 71.3 GHz @ 33% strain).
• Maintained shielding effectiveness after multiple strain cycles.

Conclusions:

• The developed LM-based thin films offer a powerful solution for EMI shielding in next-generation smart electronics.
• The absorption-dominant and stretchable nature of the devices provides advanced EMI shielding capabilities for flexible applications.
• This work presents a new paradigm for high-performance, deformable EMI shielding devices.