Controllable patterning of liquid metals via DMD-based stencil lithography for high-conductivity and stretchable electronics

Patterned liquid metals (LMs) are gaining significant attention as ideal candidate conductors for flexible and stretchable electronics due to their good conductivity and intrinsic deformability. In this work, a fabrication strategy was proposed for the facile and direct patterning of LM on various substrates without subsequent processing steps. Our approach utilizes stencil lithography based on the digital mirror device (DMD)-based light modulation technique to achieve selective adhesion of modified LM. Specifically, we introduced lithium magnesium sodium silicate (LiMgNaO 6 Si 2 ) particles as modifiers for eutectic gallium‑indium (EGaIn), resulting in a modified LM with enhanced adhesive properties. Concurrently, a DMD-based maskless lithography system was employed to fabricate patterned template on the substrates, enabling spatially selective adhesion of the modified LM to achieve the LM patterns with adequate resolution and customizable features. The as-fabricated LM conductive paths show good conductivity, stretchability, self-healing ability, electromechanical stability under different deformations, and reproducible printability without conductivity degradation. To evaluate the potential of this patterning method, a few applications such as flowing light-emitting diode (LED) systems and pressure-actuated sensing system have been demonstrated based on the resulting LM conductive paths, showing substantial application values in next-generation soft intelligent electronics and high-density flexible integrated circuits.