Analysis of stability of nano- vs micro-sized resonant tunnelling diode (RTD) devices for future neuromorphic computing applications

Al-Taai, Q. R. A. , Wang, J., Morariu, R. , Ofiare, A., Al-Khalidi, A. and Wasige, E. (2021) Analysis of stability of nano- vs micro-sized resonant tunnelling diode (RTD) devices for future neuromorphic computing applications. International Journal of Nanoelectronics and Materials, 14, pp. 149-155.

Abstract

In this paper, we report on the fabrication of micrometre and nanometre-sized resonant tunnelling diode (RTD) devices which may be used as excitable neuromorphic spike generators. The fabrication processes using photolithography were applied for micro-sized RTDs, while for nano-RTDs the fabrication was optimised to achieve accurate nano-sized mesas through a multi-exposure step based on e-beam lithography. The results show a large decrease in the peak currents from 41 mA to 27 A for micro- and nano-RTDs, respectively, peak and valley voltages of around 0.6 V and 0.8 V and a peak to valley current ratio of around 2.4. For the smallest fabricated RTD of 300 nm diameter, the expected energy consumption per oscillation cycle (if used in an oscillator) will be 1.55 fJ. DC characterisation of the devices show that the nano-RTDs are stable and have smooth current voltage (I-V) characteristics compared with micro-RTDs. The nano-RTD technology could be employed to realise highly sensitive photodetectors that can be operated as spike generators and so they could underpin the development of energy efficient neuromorphic computing.

• Item Type: Articles
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Morariu, Razvan and Ofiare, Dr Afesomeh and Al-Khalidi, Dr Abdullah and Wasige, Professor Edward and Al-Taai, Dr Qusay
• Authors: Al-Taai, Q. R. A., Wang, J., Morariu, R., Ofiare, A., Al-Khalidi, A., and Wasige, E.
• College/School: College of Science and Engineering > School of Engineering > Electronics and Nanoscale Engineering
• Journal Name: International Journal of Nanoelectronics and Materials
• Publisher: Universiti Malaysia Perlis (UniMAP)
• ISSN: 1985-5761
• ISSN (Online): 1997-4434
• Copyright Holders: Copyright © 2021 Universiti Malaysia Perlis (UniMAP)
• First Published: First published in International Journal of Nanoelectronics and Materials 14:149-155
• Publisher Policy: Reproduced with the permission of the publisher

Project Code	Award No	Project Name	Principal Investigator	Funder's Name	Funder Ref	Lead Dept
303977		ChipAI	Edward Wasige	European Commission (EC)	828841	ENG - Electronics & Nanoscale Engineering