Crater-Inspired Hollow Microdome Arrays for Linear Megapascal-Range Wearable Pressure Sensing

Abstract Reconciling high sensitivity with linearity over a broad pressure range remains a central challenge for flexible piezoresistive pressure sensors, because microstructured conductive interfaces often undergo rapid compaction under increasing pressure. Here, we report crater-inspired microdome arrays that couple a laser-roughened annular rim, hollow cavity, and inclined sidewalls to regulate staged deformation and conductive-contact evolution during compression. The architecture is fabricated by template-assisted replication followed by localized laser ablation, which converts closed microdomes into open crater-like units. Under loading, unlike solid microdomes that undergo continuous compression and flattening, the CMDA establishes localized contact through the annular rim, while the hollow cavity accommodates continued inward deformation and the high-stress region progressively extends toward the inclined sidewalls. This rim-initiated, cavity-assisted, and sidewall-supported deformation enables rapid resistance modulation at low pressure while delaying structural compaction and sustaining progressive contact evolution at high pressure. The optimized sensor delivers a linear piezoresistive response over 0–1200 kPa with a sensitivity of 158.1 kPa–1, and its applicability is demonstrated in physiological monitoring, motion sensing, and pressure-encoded human–machine interaction. This work demonstrates an open-apex microstructural strategy that spatially separates contact initiation, deformation accommodation, and load support within a single microdome, thereby providing a structural route to flexible piezoresistive sensors that combine high sensitivity with megapascal-range linearity.