Keynote Speaker
Prof. Shashi Paul
Deciphering Electrical Bistability in Nanocomposite by Electrostatic Force Microscopy
Intensive research is currently underway to exploit the highly interesting properties of nano-bits (nano-sized particles, nanowires, and organic molecules, etc) for optical, electronic, and other applications. An admixture of polymer and nanoparticles (nanocomposite) was used to realize electronic memory devices. These devices show different electrical conductance states ("high" and "low") when an electric field is applied, thus making the structures suitable for data retention. These states can be viewed as the realization of memory. We used electrostatic force microscopy (EFM) to uncover the true cause of electrical conductance states, which was an open question for over a decade ago. In this presentation, an introduction will be given to the nanocomposite electronic memory devices, contradictions in published work, and how EFM measurements have helped us realize electronic memory devices in a more predictable way. We have also observed an open-loop current-voltage (IV) behavior that can only be explained if there is electrical charging taking place of nano-particles embedded within the polymer matrix. Therefore, the EFM study was a fundamental step to argue the open-loop IV behavior in nanocomposite.
References
1. Prime, D. & Paul, S. 2010, “First contact-charging of gold nanoparticles by electrostatic force microscopy”, Applied Physics Letters, vol. 96, no. 4.
2. Paul, F., Nama Manjunatha, K., Paul, S., Non-Zero and Open-Loop Current–Voltage Characteristics in Electronic Memory Devices. Adv. Electron. Mater. 2023, 9, 2300324.
3. F. Paul and S. Paul, “Electrical Bistability by Creating an Internal Electrical Field and Its Application in Emerging Two-terminal Electronic Memory Devices“ in Advanced Memory Technology Functional Materials and Devices, ed. Y. Zhou, Royal Society of Chemistry, 2023, vol. 1, ch. 5, pp. 149-182. (DOI: 10.1039/BK9781839169946-00149
4. Paul, S. (2022) Organic and Macromolecular Memory – Nanocomposite Bistable Memory Devices. In: Chen, A. (Ed.) Advances in Semiconductor Technologies: Selected Topics Beyond Conventional CMOS, Hoboken, NJ: Wiley, pp.133-151 (DOI: 10.1002/9781119869610.ch8)
5. Paul, F. and Paul, S. To Be or Not to Be – Review of Electrical Bistability Mechanisms in Polymer Memory Devices (2022) Small, 18 (21), art. no. 2106442.