Flexible and Printed Organic Nonvolatile Memory Transistor with Bilayer Polymer Dielectrics

Abstract

In this study, printed organic nonvolatile memory thin-film transistors (TFTs) with phase-separated tunneling layer is presented. Finely patterned electrodes are fabricated by reverse-offset printing with 15 mu m line width and 10 mu m channel length. Memory devices are configured in a bottom-gate bottom-contact TFT structure with a high-k gate blocking insulator poly(vinylidene fluoride-co-trifluoroethylene). A blended ink, which consisted of a small-molecule p-type organic semiconductor dithieno[2,3-d;2 &apos;,3 &apos;-d &apos;]benzo[1,2-b;4,5-b &apos;]dithiophene and a polystyrene dielectric, is fabricated using air-pulse nozzle printing. The tunneling layer is formed during the active layer printing process with the blended ink by phase separation of small-molecule and polymer. The printed memory TFTs with the phase-separated tunneling layer exhibit significantly improved V-TH shifts (approximate to 3 times), programmed/erased current ratio (>10(3) A A(-1)), switching speed (<100 ms), and estimated data retention (>10 years). This memory device can be applied to wearable electronics, smart Internet-of-Things devices, and neuromorphic computing devices.