Interference-Free, Multimodal Electronic Skin Matrix with Low-Power, Monolithic Integrated Circuits

Abstract

An interference-free, flexible multimodal electronic skin matrix (3 x 3 pressure sensor array and four chemical sensors) combined with low-power, monolithic integrated circuits with coplanar-type thin-film transistor arrays is demonstrated to detect mechanical and chemical stimuli simultaneously. This sensing platform is facilitated by a photocrosslinked ionic polymer film including ionic liquids, a solution-processed amorphous oxide semiconductor, and a protective layer or microhole channel facilitated by a polydimethylsiloxane elastomer film. Consequently, a highly reliable piezocapacitive pressure-sensing capability under a chemical variation is achieved with an electric double layer mechanism at the interface between the ionic polymer film and electrode. Moreover, selective olfactory detection to various chemicals with high sensitivity is achieved even under a pressing atmosphere via ion-gas interactions in the chemical sensor matrix. The proposed method is expected to contribute toward the practical realization of a new class of multimodal tactile sensors that reflect human-machine interactions.