Development of Fully-printed Stretchable Devices

摘要

In recent years, stretchable fiexible electronics has become a research hotspot in the electron ics industry and academia due to its outstanding expansibility, adaptability, and portability. With the improvement of science and technology, materials science, mechanics, and manu facturing process have all achieved rapid development. Advanced technologies have made possible the manufacture of stretchable fiexible electronic devices with excellent performance.;In the first half (chapter 2) of this thesis, we developed an inkjet printing method to pattern silver nanowires (AgNWs) with length of up to ~40 m on various substrates. Well defined and uniform AgNWs features could be obtained by optimizing the printing conditions including nozzle size, ink formulation, surface energy, substrate temperature, and printing speed. Such printed AgNWs have been used to demonstrate bi-axially stretchable conductors that could maintain stable conductance under an areal strain of up to 156% (256% of its original area). By printing the AgNWs electrodes on a composite composed of PDMS and electroluminescent (EL) phosphors, I have demonstrated a printed stretchable EL display. In chapter 3, I developed a silver nanoparticles (AgNPs) based stretchable sensor for pressure sensing through directly printing AgNPs on Polyurethane Acrylate (PUA) substrate. High sensitivity is indicated while I test it within a low-pressure load. Its resistance increases 100% when a 5.5 kPa pressure is applied on it. I explored the applications of heartbeat detection and wind sensing in this work.