Stretchable Thin Film Mechanical‐Strain‐Gated Switches and Logic Gate Functions Based on a Soft Tunneling Barrier. Issue 41 (5th September 2021)

• Record Type: Journal Article
• Authors: Chae, Soosang; Choi, Won Jin; Fotev, Ivan; Bittrich, Eva; Uhlmann, Petra; Schubert, Mathias; Makarov, Denys; Wagner, Jens; Pashkin, Alexej; Fery, Andreas
• Is Part Of: Advanced materials. Volume 33:Issue 41(2021)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2021-09-05
• Subjects: logic gates -- strain‐gated electric switches -- stretchable circuits -- thin films -- tunneling; Materials -- Periodicals; Chemical vapor deposition -- Periodicals; 620.11
• DOI: 10.1002/adma.202104769
• Languages: English
• ISSNs: 0935-9648

Abstract

Abstract: Mechanical‐strain‐gated switches are cornerstone components of material‐embedded circuits that perform logic operations without using conventional electronics. This technology requires a single material system to exhibit three distinct functionalities: strain‐invariant conductivity and an increase or decrease of conductivity upon mechanical deformation. Herein, mechanical‐strain‐gated electric switches based on a thin‐film architecture that features an insulator‐to‐conductor transition when mechanically stretched are demonstrated. The conductivity changes by nine orders of magnitude over a wide range of tunable working strains (as high as 130%). The approach relies on a nanometer‐scale sandwiched bilayer Au thin film with an ultrathin poly(dimethylsiloxane) elastomeric barrier layer; applied strain alters the electron tunneling currents through the barrier. Mechanical‐force‐controlled electric logic circuits are achieved by realizing strain‐controlled basic (AND and OR) and universal (NAND and NOR) logic gates in a single system. The proposed material system can be used to fabricate material‐embedded logics of arbitrary complexity for a wide range of applications including soft robotics, wearable/implantable electronics, human–machine interfaces, and Internet of Things. Abstract : Mechanical‐strain‐gated electric switches play a key role in sensing, soft robotics, and stretchable electronics, which typically operate an "off‐switch" function—exhibiting a decrease in conductivity upon an applied strain. A thin‐film architecture that features the inverse behavior, "on‐switch": a strain‐induced transition from insulating to metallic conductivity, spanning nine orders of magnitude in conductivity, is demonstrated.