Hangbo Zhao | University of Southern California: How can we pattern highly fluid, high-surface-tension liquid metals at a 5-micron resolution without vacuum deposition?
00:06:18 - 00:07:36
Other snippets from this talk
Summary of the clip:
How can we pattern highly fluid, high-surface-tension liquid metals at a 5-micron resolution without vacuum deposition?
Liquid metals exhibit extremely high surface tension, making traditional lithographic and vacuum deposition methods impractical for high-resolution patterning. To bypass this, a novel hybrid approach combining fluidic self-assembly and elastomer-based transfer printing was developed.
The process initiates by self-assembling liquid metal microparticles onto a pre-patterned SU-8 template on a glass substrate. These particles are then transfer-printed onto a silicone elastomer, where the applied printing pressure drives localized mechanical sintering and particle rupture.
This technique successfully produces ultra-fine features with line widths down to 5 microns and thicknesses of only 2 to 3 microns. This combination of fine resolution and scalable transfer printing demonstrates high potential for wafer-scale manufacturing of stretchable circuits.
In this short video, you can learn:
* The micro-transfer printing workflow used to bypass the high surface tension limits of liquid metals.
* How templated SU-8 substrates enable ultra-fine alignment of microparticles before elastomeric transfer.
* The role of transfer pressure in mechanically driving secondary sintering of the patterned conductors.
š **Clip Abstract** This clip introduces a high-resolution transfer printing process that achieves 5-micron line widths in liquid metal circuits. By utilizing a templated assembly and mechanical transfer pressure, the method enables scalable, wafer-level patterning of highly stretchable electronics.
š Link in comments š
#LiquidMetalElectronics, #MicroTransferPrinting, #MechanicalSintering, #FluidicSelfAssembly, #StretchableElectronics, #PrintedElectronics
This is a highlight of the presentation:
High-Resolution Liquid Metal-Based Stretchable Electronics Enabled By Colloidal Self-Assembly and Micro-Transfer Printing
Future of Electronics RESHAPED USA 2026
10-11 June 2026
Computer History Museum, Mountain View, California, USA
Organised By:
TechBlick
More Highlights from the same talk.
00:03:16 - 00:05:23
Can capillary forces during solvent evaporation be harnessed to achieve room-temperature "cold welding" of liquid metal microparticles?
Can capillary forces during solvent evaporation be harnessed to achieve room-temperature "cold welding" of liquid metal microparticles?
Liquid metal microparticles are inherently insulated by a native oxide skin that prevents electrical conduction. By utilizing electrostatic self-assembly, a uniform monolayer of these particles is deposited onto a substrate in a self-limiting process.
During the drying phase, the evaporation of the surrounding liquid solvent generates capillary forces on the order of hundreds of nanonewtons. This mechanical force is strong enough to rupture the nanoscale oxide skin, enabling room-temperature cold welding between adjacent gallium-based particles.
This physical mechanism was validated using atomic force microscopy (AFM) to crush individual particles and measure the exact rupture threshold. The resulting network achieves metallic-level bulk conductivity without requiring high-temperature thermal sintering.
In this short video, you can learn:
* How electrostatic charge is leveraged to assemble a self-limiting monolayer of liquid metal microparticles.
* The role of capillary force during solvent evaporation in rupturing the native insulating oxide skin.
* How AFM nano-indentation was used to measure and prove the physical threshold of oxide rupture.
š **Clip Abstract** This clip details a self-limiting electrostatic assembly method to form highly conductive liquid metal networks at room temperature. It reveals how evaporation-induced capillary forces act as the primary mechanism for breaking native oxide skins, initiating spontaneous cold welding.
š Link in comments š
#LiquidMetalMicroparticles, #ElectrostaticSelfAssembly, #CapillaryColdWelding, #OxideSkinRupture, #FlexibleElectronics, #PrintedElectronics
00:08:14 - 00:09:40
Why does this liquid metal conductor become more conductive the further you stretch it?
Why does this liquid metal conductor become more conductive the further you stretch it?
Conventional stretchable conductors experience a sharp rise in resistance under strain due to geometric deformation and cross-sectional narrowing. However, this liquid metal particle film exhibits highly anomalous electromechanical behavior, maintaining nearly constant resistance up to 1,300% strain.
This unique property is governed by a dynamic morphological transition. As the underlying elastomer is stretched, the semi-solid liquid metal microparticles deform and rupture their remaining oxide shells, actively forming a more dense and interconnected metallic path.
This self-healing conductive network compensates for the geometric path elongation, leading to the lowest resistance variation among modern stretchable conductors. This behavior is ideal for building ultra-stable stretchable sensors and medical interconnects.
In this short video, you can learn:
* The physics behind the anomalous, low-resistance changes of liquid metal networks under high strain.
* How stretch-induced particle rupture creates new, highly conductive internal pathways.
* Why this material's electromechanical properties outperform traditional nanowire and elastomer composites.
š **Clip Abstract** This clip explains the counter-intuitive electromechanical properties of liquid metal microparticle films under extreme strain. It illustrates how physical stretching drives the continuous rupture and coalescence of particles, maintaining ultra-stable conductivity up to 1,300% strain.
š Link in comments š
#LiquidMetalMicroparticles, #StretchableConductors, #StretchInducedCoalescence, #SelfHealingConductiveNetworks, #StretchableElectronics, #WearableSensors