Cardiff University | Prifysgol Caerdydd ORCA
Online Research @ Cardiff 
WelshClear Cookie - decide language by browser settings

Modeling and simulation of ultrahigh sensitive AlGaN/AlN/GaN HEMT based hydrogen gas detector with low detection limit

Varghese, Arathy, Eblabla, Abdalla ORCID: and Elgaid, Khaled ORCID: 2021. Modeling and simulation of ultrahigh sensitive AlGaN/AlN/GaN HEMT based hydrogen gas detector with low detection limit. IEEE Sensors Journal 21 (13) , pp. 15361-15368. 10.1109/JSEN.2021.3072476

[thumbnail of FINAL VERSION.pdf]
PDF - Accepted Post-Print Version
Download (1MB) | Preview


Presented through this work is a steady state analytical model of the GaN HEMT based gas detector. GaN with high chemical and thermal stability provides promises for detectors in hazardous environments. However, HEMT sensor resolution must be improved to develop high precision gas sensors for automotive and space applications. The proposed model aids in systematical study of the sensor performance and prediction of sensitivities. The linear relation of threshold voltage shift at thermal equilibrium is used in predicting the sensor response. Numerical model for the reaction rates and the electrical dipole at the adsorption sites at the surface and metal/semiconductor interface have been developed and the sensor performance is analyzed for various gas concentrations. The validation of the model has been achieved through surface and interfacial charge adsorption-based gate electrode work function, Schottky barrier, 2DEG and threshold voltage deduction using MATLAB and SILVACO ATLAS TCAD. Further the applicability of gd (channel conductance) as gas sensing metric is also presented. With high ID and gd percentile sensitivities of 118.5% and 92 % for 10 ppm hydrogen concentration. The sensor shows capability for detection in sub-ppm levels by exhibiting a response of 0.043% for 0.01ppm (10 ppb) hydrogen concentration. The detection limit of the sensor (1% sensitivity) presented here is 169 ppb and the device current increases by 34.2 μA for 1ppb hydrogen concentration.

Item Type: Article
Date Type: Publication
Status: Published
Schools: Engineering
Publisher: Institute of Electrical and Electronics Engineers (IEEE)
ISSN: 1530-437X
Date of First Compliant Deposit: 5 May 2021
Date of Acceptance: 6 April 2021
Last Modified: 06 Jan 2024 02:07

Citation Data

Cited 4 times in Scopus. View in Scopus. Powered By Scopus® Data

Actions (repository staff only)

Edit Item Edit Item


Downloads per month over past year

View more statistics