Stretchable Conductors Fabricated by Stencil Lithography and Centrifugal Force-Assisted Patterning of Liquid Metal

Flexible and stretchable conductors are critical elements for constructing soft electronic systems and have recently attracted tremendous attention. Next generation electronic devices call for self-healing conductors that can mimic the...

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Low-Cost Rapid Fabrication of Conformal Liquid-Metal Patterns

Applied Sciences ◽

10.3390/app9081565 ◽

2019 ◽

Vol 9 (8) ◽

pp. 1565 ◽

Cited By ~ 3

Author(s):

Elassy ◽

Akau ◽

Shiroma ◽

Seo ◽

Ohta

Keyword(s):

Liquid Metal ◽

Flexible Electronics ◽

Communication Systems ◽

Liquid Metals ◽

Low Cost ◽

Spray Coating ◽

Uv Curable ◽

Rapid Fabrication ◽

Communication Devices ◽

Stretchable Conductors

Patterned conformal conductive structures are used to realize flexible electronics for applications such as electronic skin, communication devices, and sensors. Thus, there is a demand for low-cost rapid fabrication techniques for flexible and stretchable conductors. Spray-coating of liquid metals is a prototyping method that is compatible with elastic substrates. In this work, UV-curable and polyimide masks were used to pattern sprayed liquid metal (LM). The effect of the spraying parameters on the thickness and conductivity of the LM was characterized. A minimum LM linewidth of 48 µm was achieved, along with a minimum gap width of 34 µm. A LM patch antenna and transmission line, which can potentially be used for communication systems, were demonstrated using this fabrication process.

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Self-sintering liquid metal colloidal inks for facile manufacture of stretchable conductors

2020 3rd IEEE International Conference on Soft Robotics (RoboSoft) ◽

10.1109/robosoft48309.2020.9116043 ◽

2020 ◽

Author(s):

Michelle C. Yuen ◽

Megan A. Creighton ◽

Christopher E. Tabor

Keyword(s):

Liquid Metal ◽

Stretchable Conductors

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3D-Printed Liquid Metal-based Stretchable Conductors and Pressure Sensors

Smart Materials and Structures ◽

10.1088/1361-665x/ac15a1 ◽

2021 ◽

Author(s):

Thassyo Pinto ◽

Claudia Chen ◽

Cody Pinger ◽

Xiaobo Tan

Keyword(s):

Liquid Metal ◽

Pressure Sensors ◽

Stretchable Conductors ◽

3D Printed

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Aerosol Spray Deposition of Liquid Metal and Elastomer Coatings for Rapid Processing of Stretchable Electronics

Micromachines ◽

10.3390/mi12020146 ◽

2021 ◽

Vol 12 (2) ◽

pp. 146

Author(s):

Taylor Neumann ◽

Berra Kara ◽

Yasaman Sargolzaeiaval ◽

Sooik Im ◽

Jinwoo Ma ◽

...

Keyword(s):

Liquid Metal ◽

Liquid Metals ◽

Spray Deposition ◽

Stretchable Electronics ◽

Conformal Coating ◽

Aerosol Spray ◽

Stretchable Conductors ◽

Merging Process ◽

Pass Through ◽

Stretchable Sensors

We report a spray deposition technique for patterning liquid metal alloys to form stretchable conductors, which can then be encapsulated in silicone elastomers via the same spraying procedure. While spraying has been used previously to deposit many materials, including liquid metals, this work focuses on quantifying the spraying process and combining it with silicones. Spraying generates liquid metal microparticles (~5 μm diameter) that pass through openings in a stencil to produce traces with high resolution (~300 µm resolution using stencils from a craft cutter) on a substrate. The spraying produces sufficient kinetic energy (~14 m/s) to distort the particles on impact, which allows them to merge together. This merging process depends on both particle size and velocity. Particles of similar size do not merge when cast as a film. Likewise, smaller particles (<1 µm) moving at the same speed do not rupture on impact either, though calculations suggest that such particles could rupture at higher velocities. The liquid metal features can be encased by spraying uncured silicone elastomer from a volatile solvent to form a conformal coating that does not disrupt the liquid metal features during spraying. Alternating layers of liquid metal and elastomer may be patterned sequentially to build multilayer devices, such as soft and stretchable sensors.

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Rupture stress of liquid metal nanoparticles and their applications in stretchable conductors and dielectrics

npj Flexible Electronics ◽

10.1038/s41528-021-00108-w ◽

2021 ◽

Vol 5 (1) ◽

Author(s):

Yang Liu ◽

Xinyi Ji ◽

Jiajie Liang

Keyword(s):

Dielectric Constant ◽

Liquid Metal ◽

Metal Nanoparticles ◽

Oxide Shell ◽

Stretchable Electronics ◽

Shore Hardness ◽

Rupture Stress ◽

Stretchable Conductors ◽

Different Diameters ◽

The Relationship

AbstractFew works had systematically investigated the relationship between the rupture stress of the oxide shell and the diameter of liquid metal nanoparticles (LMNPs). Here, we fabricated a series of elastomer/LMNPs composites, which were based on various polyurethanes with different shore hardness and LMNPs with different diameters, to systematically study the rupture stress of LMNPs. We established a reliable and guidable relationship between the stress–strain curves of elastomers with different shore hardness and rupture stress of LMNPs with various diameters by both experiments and numerical calculations. Based on this guidance, we can facilely prepare stretchable conductors with remarkable stretchability and conductivity (i.e., 24,130 S · cm−1 at 500% strain) and stretchable dielectrics with excellent stretchability and permittivity (i.e., dielectric constant of 76.8 with 580% strain) through controlling the shore hardness of elastomers and diameter of LMNPs. This work will facilitate the systematic study of LMNPs and expand their use in stretchable electronics.

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