Regulated liquid metal via semiconductor valve toward highly stretchable topological circuits

Wearable electronics with complex circuits and three-dimensional (3D) structure are indispensable to advanced next-generation flexible technologies like e-skins and soft robotics. However, fabricating 3D flexible electronics remains challenging, primarily due to the difficulty in obtaining highly stretchable materials with precise current control and complex topological structures. This work reports a unidirectional conductive semiconductor valve in liquid metals (LM-SV) constructed via interfacial barrier engineering to enable soft, complex topological circuits. The LM-SV exhibits ultrahigh stretchability (~1000% strain), robust unidirectional conductivity over 1000 cycles at 500% strain, and stable operation across wide temperature ( − 5–100 °C) and frequency (1 Hz – 5 MHz) ranges. Switching voltages (0.43—0.80 V) are conveniently tunable through LM composition modulation. Leveraging these features, LM-SV circuits can be topologically reconfigured from 2D layouts into 3D architectures with real-time functional switching. Furthermore, a wirelessly powered stretchable logic circuit demonstrates the potential of this LM-SV strategy for advanced flexible electronic systems. Fabricating 3D flexible electronics is challenging due to the difficulty in obtaining highly stretchable materials with precise current control and complex topological structures. Here, the authors report a unidirectional conductive semiconductor valve in liquid metals for soft, complex topological circuits.