Ultrafast and Mold‐Free Fabrication of Tactile Sensors via Pixel‐Level Sequential Grayscale Digital Light Processing Printing

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The development of flexible tactile sensors has been constrained by fabrication methods that are often complex, costly, and limited in design flexibility. In this study, a fully printed, mold‐free, ultrafast, and scalable fabrication strategy is presented, based on sequential grayscale digital light processing (s‐gDLP) printing. A dual‐exposure UV process with pixel‐level grayscale modulation is employed to construct hierarchical microstructures within 6 seconds, followed by the direct deposition of conductive layers without the need for molds or vacuum‐based techniques. A dome‐shaped architecture with a 60 µm micro‐gap is formed, enabling a tactile switching mechanism that suppresses baseline current and results in ultrahigh sensitivity (10,692 kPa −1 ), rapid response (0.09 s), and low power consumption (0.01 V). Grayscale‐modulated masks are utilized to precisely define microstructural features, allowing for the customization of sensors capable of detecting multidirectional forces, including shear and bending. The scalability of the process is demonstrated through the fabrication of 5 × 5 sensor arrays with uniform conductive layer patterning, exhibiting stable performance under both static and dynamic loading conditions, with minimal signal crosstalk (1.6%). Through this work, s‐gDLP is showcased as a transformative additive manufacturing tool for the production of flexible, wearable sensors and soft microelectronic devices.