Comparative Study of Al2O3 and HfO2 as gate dielectric on AlGaN/GaN MOSHEMTs

Karami, K. , Hassan, S., Taking, S., Ofiare, A., Dhongde, A., Al-Khalidi, A. and Wasige, E. (2023) Comparative Study of Al2O3 and HfO2 as gate dielectric on AlGaN/GaN MOSHEMTs. International Journal of Electronics and Communication Engineering, 17(2), pp. 47-50.

Abstract

We have made a comparative study on the influence of Al2O3 and HfO2 grown using Atomic Layer Deposition (ALD) technique as dielectric in the AlGaN/GaN metal oxide semiconductor high electron mobility transistor (MOS-HEMT) structure. Five samples consisting of 20 nm and 10 nm each of A2lO3 and HfO2 respectively and a Schottky gate HEMT, were fabricated and measured. The threshold voltage shifts towards negative by 0.1 V and 1.8 V for 10 nm thick HfO2 and 10 nm thick Al2O3 gate dielectric layers, respectively. The negative shift for the 20 nm HfO2 and 20 nm Al2O3 were 1.2 V and 4.9 V, respectively. Higher gm/IDS (transconductance to drain current) ratio was also obtained in HfO2 than Al2O3. With both materials as dielectric, a significant reduction in the gate leakage current in the order of 104 was obtained compared to the sample without the dielectric material.

• Item Type: Articles
• Additional Information: This work was supported in part by EPSRC grant no. EP/R024413/1.
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Wasige, Professor Edward and Dhongde, Aniket and Al-Khalidi, Dr Abdullah and Hassan, Sahalu and Karami, Mr Kaivan and Ofiare, Dr Afesomeh
• Authors: Karami, K., Hassan, S., Taking, S., Ofiare, A., Dhongde, 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 Electronics and Communication Engineering
• Publisher: World Academy of Science, Engineering and Technology
• ISSN: 1307-6892

Project Code	Award No	Project Name	Principal Investigator	Funder's Name	Funder Ref	Lead Dept
301178		Novel GaN Power Devices and Packaging Technologies for 300 degC Ambient Operation	Edward Wasige	Engineering and Physical Sciences Research Council (EPSRC)	EP/R024413/1	ENG - Electronics & Nanoscale Engineering