Transfer Printing and Reconfiguration of Soft Electronics Using Digital Microfluidics and Laser Machining

ABSTRACT Liquid phases represent the softest class of materials and therefore offer unique characteristics for damage‐free transfer printing of ultrathin semiconductor nanomembranes for flexible and stretchable electronics. Existing liquid‐assisted approaches, particularly those based on liquid metals, however, face several limitations, including the need for a detachable membrane on a donor substrate, potential residual contamination, and complex thermal or laser‐assisted release processes. We present here a preload‐free, droplet‐based transfer‐printing strategy that combines rapid laser patterning with digital microfluidics to enable cleanroom‐free collection, transport, and assembly of 2D nanomembranes onto planar and curved substrates. The implementation of liquid surface tension and droplet actuation enabled by embedded ferromagnetic microbeads provides intrinsic self‐balancing on the droplet apex, self‐alignment with the collecting substrate's footprint, and precise positioning of membranes with intimate conformal contact to 3D surfaces. Through digital microfluidic manipulation, mobile droplets carrying functional membranes can search for, engage, and interface with targeted 3D biological structures, opening a new paradigm of active, reconfigurable sensors. Demonstrations across a range of device classes, including robotics sensors, optically tunable microprisms, and soft electrodes for heart tissues, establish digital droplet‐assisted transfer as a versatile, contamination‐free strategy for integration of heterogeneous materials into flexible, 3D conformal bio‐integrated electronics systems.