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Electronic systems possessing skin-like morphology and functionalities (electronicskins [e-skins]) have attracted considerable attention in recent years to provide sensory or haptic feedback in growing areas such as robotics, prosthetics, and interactive systems. However, the main focus thus far has been on the distributed pressure or force sensors. Herein a thermoreceptive e-skin with biological systems like functionality is presented. The soft, distributed, and highly sensitive miniaturized (≈700µm2) artificial thermoreceptors (ATRs) in the e-skin are developed using an innovative fabrication route that involves dielectrophoretic assembly of oriented vanadium pentoxide nanowires at defined locations and high-resolution electrohydrodynamic printing. Inspired from the skin morphology, the ATRs are embedded in a thermally insulating soft nanosilica/epoxy polymeric layer and yet they exhibit excellent thermal sensitivity (−1.1±0.3%°C−1), fast response (≈1s), exceptional stability (negligible hysteresis for >5h operation), and mechanical durability (up to 10000bending and twisting loading cycles). Finally, the developed e-skin is integrated on the fingertip of a robotic hand and a biological system like reflex is demonstrated in response to temperature stimuli via localized learning at the hardware level.

This paper presents ultrathin chips (UTCs) based flexible tactile sensing system for dynamic contact pressure measurement. The device comprises of an AlN piezocapacitor based UTCs tightly coupled with another UTCs having metal-oxide-semiconductor field-effect transistors (MOSFETs). In this arrangement the AlN piezocapacitor forms the extended gate of MOSFETs. Both AlN piezocapacitor and MOSFET based UTCs are obtained by post-process reduction of wafer thicknesses to ~35μm using backside lapping. The performances of both UTCs were evaluated both before and after thinning and there was no noticeable performance degradation. The UTC-based AlN piezocapacitor exhibited six times higher sensitivity (43.79mV/N) than the thin filmbased AlN sensors. When coupled with MOSFETs based UTC, the observed sensitivity was 0.43N-1. The excellent performance, flexible form factor and compactness shows the potential of presented device in applications such minimal invasive surgical instruments where high-resolution tactile feedback is much needed.