Flexible 3D Architectured Piezo/Thermoelectric Bimodal Tactile Sensor Array for E‐Skin Application

TLDR

Electronic skin promises health monitoring and robotic touch sensing, yet accurately distinguishing diverse tactile inputs remains a major challenge. This work develops a vertically architectured, bimodal pressure/temperature sensor fabricated by laser processing and screen printing of all‑organic piezoelectric and thermoelectric materials for multifunctional e‑skin. The sensor is built via 3D laser‑fabricated microstructures and screen‑printed layers, with finite‑element analysis guiding thermal harvesting and demonstrating stable operation in various temperature/stress scenarios. It produces independent electrical signals for pressure and temperature, achieving 109.4 µV K⁻¹ sensitivity, 0.37 s response, 100 Pa–20 kPa pressure range, and a 4×4 array that maps spatial signals without external power.

Abstract

Abstract Electronic skin (e‐skin) functions as human–machines interaction interfaces, holding great promise in future personal health monitoring and endowing robots with capability of sense of touch. Despite recent exciting progress in e‐skin research, accurate discrimination of various tactile inputs remains a great challenge yet. A 3D processing technique is demonstrated here combining laser fabrication and screen printing to construct vertically architectured pressure/temperature bimodal active sensor employing all organic functional materials, i.e., piezoelectric poly(vinylidene fluoride‐ co ‐trifluoroethylene) and thermoelectric polyaniline‐based composites. The sensor transforms pressure and temperature stimuli into two independent electrical signals without interference, exhibiting high temperature sensing sensitivity (109.4 µV K −1 ) with rapid response time (0.37 s) and superior pressure sensing sensitivity over a wide range (100 Pa to 20 kPa). Finite element analyses further explain the thermal harvesting performance of the sensor. Applications of sensor as e‐skin in various temperature/stress perception scenarios and its stability are demonstrated. Further, a 4 × 4 pixel bimodal tactile sensor array is integrated for the first time, presenting accurate spatial distribution mapping of pressure/temperature signals simultaneously without interference, and functions without external power supply due to its intrinsic working principle. This study thus moves a step toward multifunctional flexible electronics for e‐skin applications.