title: An All-Organic Composite System for Resistive Change Memory via the Self-Assembly of Plastic-Crystalline Molecules.
abstract: An all-organic composite system was introduced as an active component for organic resistive memory applications. The active layer was prepared by mixing a highly polar plastic-crystalline organic molecule (succinonitrile, SN) into an insulating polymer (poly(methyl methacrylate), PMMA). As increasing concentrations of SN from 0 to 3.0 wt % were added to solutions of different concentrations of PMMA, we observed distinguishable microscopic surface structures on blended films of SN and PMMA at certain concentrations after the spin-casting process. The structures were organic dormant volcanos composed of micron-scale PMMA craters and disk type SN lava. Atomic force microscopy (AFM), cross-sectional transmission electron microscopy (TEM), scanning electron microscopy (SEM), and energy dispersive X-ray spectrometer (EDX) analysis showed that these structures were located in the middle of the film. Self-assembly of the plastic-crystalline molecules resulted in the phase separation of the SN:PMMA mixture during solvent evaporation. The organic craters remained at the surface after the spin-casting process, indicative of the formation of an all-organic composite film. Because one organic crater contains one SN disk, our system has a coplanar monolayer disk composite system, indicative of the simplest composite type of organic memory system. Current-voltage (I-V) characteristics of the composite films with organic craters revealed that our all-organic composite system showed unipolar type resistive switching behavior. From logarithmic I-V characteristics, we found that the current flow was governed by space charge limited current (SCLC). From these results, we believe that a plastic-crystalline molecule-polymer composite system is one of the most reliable ways to develop organic composite systems as potential candidates for the active components of organic resistive memory applications.
authors.affiliation: Applied Quantum Composites Research Center, Institute of Advanced Composite Materials, Korea Institute of Science and Technology , Jeollabuk-do 55324, Republic of Korea.
authors.forename: An-Na
authors.initials: AN
authors.lastname: Cha
authors.affiliation: Applied Quantum Composites Research Center, Institute of Advanced Composite Materials, Korea Institute of Science and Technology , Jeollabuk-do 55324, Republic of Korea.|Department of Polymer-Nano Science and Technology, Chonbuk National University , Jeonju 561-756, Republic of Korea.
authors.forename: Sang-A
authors.initials: SA
authors.lastname: Lee
authors.affiliation: Applied Quantum Composites Research Center, Institute of Advanced Composite Materials, Korea Institute of Science and Technology , Jeollabuk-do 55324, Republic of Korea.
authors.forename: Sukang
authors.identifier: http://orcid.org/0000-0002-3019-0584
authors.initials: S
authors.lastname: Bae
authors.affiliation: Applied Quantum Composites Research Center, Institute of Advanced Composite Materials, Korea Institute of Science and Technology , Jeollabuk-do 55324, Republic of Korea.
authors.forename: Sang Hyun
authors.initials: SH
authors.lastname: Lee
authors.affiliation: Applied Quantum Composites Research Center, Institute of Advanced Composite Materials, Korea Institute of Science and Technology , Jeollabuk-do 55324, Republic of Korea.
authors.forename: Dong Su
authors.initials: DS
authors.lastname: Lee
authors.affiliation: KU-KIST Graduate School of Converging Science and Technology, Korea University , Seoul 136-701, Republic of Korea.
authors.forename: Gunuk
authors.initials: G
authors.lastname: Wang
authors.affiliation: Applied Quantum Composites Research Center, Institute of Advanced Composite Materials, Korea Institute of Science and Technology , Jeollabuk-do 55324, Republic of Korea.
authors.forename: Tae-Wook
authors.identifier: http://orcid.org/0000-0003-2157-732X
authors.initials: TW
authors.lastname: Kim
keywords: organic composites; organic craters; organic disk; resistive change memory; space charge limited current; succinonitrile