All-Polymer Bistable Resistive Memory Device Based on Nanoscale Phase-Separated PCBM-Ferroelectric Blends

• Published in: Advanced functional materials Vol. 23; no. 17; pp. 2145 - 2152
• Main Authors: Khan, M. A., Bhansali, Unnat S., Cha, Dongkyu, Alshareef, H. N.
• Format: Journal Article
• Language: English
• Published: Weinheim WILEY-VCH Verlag 06-05-2013; WILEY‐VCH Verlag
• Subjects: blend; Blends; Data storage; Devices; Electrodes; ferroelectric; Ferroelectric materials; Ferroelectricity; memory; Nanostructure; PCBM; polymer; Polymer blends
• ISSN: 1616-301X; 1616-3028
• DOI: 10.1002/adfm.201202724

All polymer nonvolatile bistable memory devices are fabricated from blends of ferroelectric poly(vinylidenefluoride–trifluoroethylene (P(VDF‐TrFE)) and n‐type semiconducting [6,6]‐phenyl‐C61‐butyric acid methyl ester (PCBM). The nanoscale phase separated films consist of PCBM domains that extend from bottom to top electrode, surrounded by a ferroelectric P(VDF‐TrFE) matrix. Highly conducting poly(3,4‐ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) polymer electrodes are used to engineer band offsets at the interfaces. The devices display resistive switching behavior due to modulation of this injection barrier. With careful optimization of the solvent and processing conditions, it is possible to spin cast very smooth blend films (Rrms ≈ 7.94 nm) and with good reproducibility. The devices exhibit high Ion/Ioff ratios (≈3 × 103), low read voltages (≈5 V), excellent dielectric response at high frequencies (ϵr ≈ 8.3 at 1 MHz), and excellent retention characteristics up to 10 000 s.
All‐polymer nonvolatile resitive memory devices are fabricated using a blend of ferroelectric poly(vinylidenefluoride–trifluoroethylene (P(VDF‐TrFE)) and n‐type semiconducting [6,6]‐phenyl‐C61‐butyric acid methyl ester (PCBM) with doped poly(3,4‐ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) electrodes. The nanometer‐scale phase separated films consist of PCBM domains that extend from the bottom to the top electrode, surrounded by a ferroelectric P(VDF‐TrFE) matrix. The devices show excellent performance with good ON/OFF ratios, low read voltages, and long retention times.