Advances in direct ink writing techniques are helping to reshape the way electronic devices are fabricated.
BSAC Co-Director Liwei Lin and colleagues are leading advancements in additive manufacturing with a new laser-assisted direct ink writing technique, recently featured in Nature Electronics and TechXplore. By utilizing a laser to instantly cure thermoset materials as they are extruded, this method eliminates the need for support structures and enables the "volumetric programming" of mechanical stiffness and conductivity. Ultimately, this technology overcomes traditional fabrication limits to facilitate the next generation of flexible sensors and devices.
Writing electronics
Read more in Nature Electronics | 24 November 2025 (linked)
Direct ink writing is an additive manufacturing technique that builds structures layer by layer, in contrast to traditional subtractive methods that remove materials in order to shape an object. Like writing with a pen, the process involves extruding a formulated ink through a fine nozzle and laying it down directly onto a substrate in a controlled pattern. A key advantage of the approach is its compatibility with different material systems, including conducting, semiconducting and insulating materials1. It can also be used to construct complex three-dimensional geometries that would be difficult — or, in fact, impossible — to achieve with other methods....
Laser-assisted 3D printing can fabricate free-standing thermoset-based electronics in seconds
Read more in TechXplore | 01 December 2025 (linked)
"Free-standing thermoset devices offer two unique advantages," said Liwei Lin, co-senior author of the paper.
"First, the in-situ laser curing process eliminates the scheme used in conventional 3D processes by the supporting materials and post-process to remove the supporting structures.
"This enables the efficient fabrication of complex 3D geometries and broader device functionality. Second, the properties of printed 3D structures are programmable. For example, the local mechanical stiffness and electrical conductivity can be adjusted by the printing parameters so that different regions can be made softer or stiffer, and their conductivity can be high or low."
The careful engineering of specific properties in specific parts of a structure could be particularly valuable when developing systems that can benefit from being stiffer or softer in different places. For example, it could be useful to develop comfortable wearable devices or functional robots with flexible joints that can conduct electricity in some parts of their body and not in others.
"To tailor the structures' properties, we focus a 1,064-nm laser on the polymer jet near the nozzle tip, where the in-situ localized gelation of the thermoset ink is induced based on the photothermal effect," explains Lin....