| PhD Viva


Name of the Speaker: Mr. Sourodeep Roy (EE19D414)
Guide: Dr. Bhaswar Chakrabarti
Co-Guide: Dr. Enakshi Bhattacharya
Online meeting link: https://meet.google.com/wsq-ozex-sdw
Date/Time: 6th February 2025 (Thursday), 4:30 PM
Title: SiO x -based resistive switching devices for brain-inspired computation

Abstract :

Resistive Random-Access Memories (RRAMs), as a class of emerging non-volatile memory technologies, have garnered significant interest for their applications in embedded memories and memory-centric computational frameworks. Despite their promise in terms of high-density storage, fast program/erase operation and low fabrication complexity, metal-oxide RRAMs have suffered from performance variability, relatively poor endurance (in comparison to DRAM or SRAM), and strong non-linearity in conductance tuning. These issues are primarily rooted in the filamentary switching mechanism of mainstream metal-oxide RRAM devices. As a result, development of RRAM devices with alternative switching mechanism(s) can be crucial for mitigating these challenges. This work presents a systematic investigation of SiO x -based resistance switching devices. The devices employ Plasma-Enhanced Chemical Vapor Deposited (PECVD) SiO x as the active switching layer, Au bottom electrode and Ti/Au top electrode in a crossbar geometry. An interplay between filamentary and interfacial switching mechanism is observed and switching becomes interface dominated at lower operating currents. The devices exhibit highly uniform switching with analog and linear conductance tunability, along with nanosecond switching speed and robust endurance. A change in the switching behavior from non-volatile to volatile is observed with the change in SiO x deposition conditions. The volatile resistive switches are used to emulate functionalities of biological dendrites. Such artificial dendrites can be used to enhance energy efficiency in neural networks. Finally, an application of volatile resistance switching in relaxation oscillators is also explored.