Conjugated fluorene based rod-coil block copolymers and their PCBM composites for resistive memory switching devices
Journal
ACS Applied Materials and Interfaces
Journal Volume
3
Journal Issue
11
Pages
4504-4511
Date Issued
2011
Author(s)
Abstract
We report the fabrication and characterization of polymer resistive switching memory devices fabricated from conjugated rod-coil poly[2,7-(9,9-dihexylfluorene)]-block-poly(2-vinylpyridine) diblock copolymers (PF-b-P2VP) and their hybrids with [6,6]-phenyl-C61-butyric acid methyl ester (PCBM). PF10-b-P2VP37 and PF 10-b-P2VP68-based devices exhibited the volatile static random access memory (SRAM) characteristic with an ON/OFF current ratio up to 1 × 107, which was explained by the trapping/back transferring of charge carrier. PF10-b-P2VP68 had a longer holding time in the ON state than PF10-b-P2VP37 because of the delayed back transfer of trapping carriers originally from the longer P2VP blocks. The PCBM aggregated size in the composite thin films were effectively reduced by PF-b-P2VP compared to the homopolymer of PF or P2VP, because of the supramolecular charge transfer interaction, as evidenced by absorption and photoluminescence spectra. Their PCBM/PF-b-P2VP composite devices changed from the nonvolatile write-once-read-many-times (WORM) memory to the conductor behavior as the PCBM composition was increased. The electric-field induced charge transfer effect enabled the electrical bistable states for the applications in digital WORM memory device. The tunable memory characteristics through the block length ratio of block copolymers or PCBM composition provided the solution-processable charge storage nanomaterials for programmable high density memory device with a reducing bit cell size. © 2011 American Chemical Society.
SDGs
Other Subjects
2-vinylpyridine; 9 ,9-dihexylfluorene; Absorption and photoluminescence; Back transfer; Bit cell; Block lengths; Charge storage; Charge transfer interaction; composite; Composite thin films; Electrical bistable; Fluorenes; High density memory; Holding time; memory; Memory device; Memory switching; Methyl esters; Non-volatile; ON/OFF current ratio; Resistive switching; Resistive switching memories; Rod-coil; Rod-coil block copolymer; Static random access memory; Block copolymers; Butyric acid; Charge transfer; Composite films; Computer crime; Conjugated polymers; Equipment; Fatty acids; Fluorine containing polymers; Fullerenes; Photoluminescence; Switching systems; Static random access storage
Type
journal article