Printed Memristive Devices for Electrical Switching and Memory Applications

Abstract

The research work reveals the engineering of ZrO2 & polymer-based sandwiched structures for resistive switching applications. The fabrication of devices was performed by electrohydrodynamic printing (EHDP) and spin coating techniques. The jetting mode of the EHDP was used for the patterning of bottom and top electrodes. The atomization mode of EDHP and spin coating techniques were used for the deposition of thin sandwiched layers between bottom and top electrodes. Fabrication of the resistive switches was done on glass, polyethylene Terephthalate (PET), and polyimide (PI) substrates. Electrically conducting material including indium tin oxide (ITO) and silver (Ag) were used as electrodes, while zirconium dioxide (ZrO2), poly(4-vinylphenol) (PVP), poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) and poly[2-methoxy-5-(2'-ethylhexyloxy)?(p-phenylenevinylene)] (MEH:PPV) were used for the deposition of sandwiched layers between bottom and top electrodes. Full organic resistive switches (FORS) were also fabricated with the sandwiched structure of PEDOT:PSS/PVP/PEDOT:PSS on a PI substrate. The fabricated resistive switches were morphologically characterized with field emission scanning electron microscope (FESEM) and focused ionic beam (FIB) techniques. Chemically composition was confirmed using x-ray diffraction (XRD) and x-ray photoelectron spectroscopy (XPS) techniques. Electrically characterization of the fabricated devices was done using semiconductor device analyzer. The sandwiched structures exhibited at least two distinct states when were being forced with opposite polarity at its electrodes. The change in the resistance was then exploited for the electrical switching and memory applications. Characterization results showed high degree of uniformity in deposited structures. The fabricated devices performed exceptionally well in bipolar resistive switching regime with a reasonable high OFF/ON ratio, endurance test, and retention time. Effect of compliance current was examined to measure the electrical switching capability of the fabricated resistive devices. Resistive switching mechanisms were also investigated for reliable application of the fabricated devices in printed electronics. The obtained results show the promising feasibility of the fabricated switches for electrical switching and memory applications in printed electronics. Current conduction mechanisms in the fabricated resistive switches were concluded based on slope calculation and were supported with the governing physical current conduction laws.