Ultrathin, solvent-resistant dielectric for monolithic fabrication of low-power, intrinsically stretchable active-matrix electronic skin

Abstract

High-performance materials are crucial for transitioning intrinsically stretchable transistors to reliable system-level circuits in electronic skin. Conventional organic dielectrics face many challenges like low solvent resistance and difficulty in securing sufficient insulating performance while keeping the dielectric thickness minimal, hindering their integration into monolithic fabrication processes. Here, we report an ultrathin, solvent-resistant, stretchable polymer dielectric synthesized via vapor-phase copolymerization of tetrahydrofurfuryl acrylate and di(ethylene glycol) divinyl ether. The copolymer film exhibits exceptional dielectric performance featuring a breakdown field exceeding 3 MV/cm and low leakage current (<4 × 10−8 A/cm2) at 125-nm thickness. Such performance is stably maintained under 80% strain and during 1,000 cycles of repeated stretching. Moreover, superior solvent resistance enables monolithic fabrication of an active-matrix electronic skin system with individual stretchable thin-film transistors, showcasing low-power operation (<10 V) under 50% strain and hysteresis-free transfer characteristics. The areal uniformity of active-matrix array is confirmed using a customized multiplexing system.