Local ferroelectric studies on interconnected PVDF nano-dot thin films using piezo force microscopy

• Published in: Journal of materials science. Materials in electronics 2019-12, Vol.30 (23), p.20716-20724
• Main Authors: Ravi Sankar, M. S., Pramod, K., Gangineni, Ramesh Babu
• Format: Article
• Language: English
• Subjects: Characterization and Evaluation of Materials; Chemistry and Materials Science; Deoxidizing; Ferroelectric domains; Ferroelectric materials; Ferroelectricity; Gamma phase; Materials Science; Memory devices; Microscopy; Optical and Electronic Materials; Self-assembly; Switches; Thin films
• ISSN: 0957-4522; 1573-482X
• DOI: 10.1007/s10854-019-02464-w

The local ferroelectric domain structure of interconnected PVDF nano-dots with applied DC voltages of ± 10 V to ± 100 V is evaluated using various Piezo force microscopy (PFM) methods such as conventional PFM and Dynamic contact electrostatic force microscopy (DC-EFM). The self-assembled PVDF nano-dots are fabricated by using a spin coater method with 2 wt% of PVDF-DMSO solution. The polar gamma phase is found to be induced by the microstructural confinement of PVDF monomers and also reveals a strong ferroelectric nature after poling at different DC bias voltages. Poling with altered directions of the voltages renders a 180° phase reversal of PVDF domains. The local domain study depicts that each nano-dot is functioning as a single domain and switches as a whole. The single nano-dot switching signifies the potential of using the nano-dots for organic ferroelectric memory devices.