Unveiling the Self-Heating and Process Variation Reliability of a Junctionless FinFET-based Hydrogen Gas Sensor

• Published in: IEEE sensors letters 2023-09, Vol.7 (9), p.1-4
• Main Authors: Gandhi, Navneet, Rathore, Sunil, Jaisawal, Rajeewa Kumar, Kondekar, P. N., Dey, Sayan, Bagga, Navjeet
• Format: Article
• Language: English
• Subjects: CAD; Computer aided design; Environmental monitoring; Field effect transistors; Gas detectors; Gas sensors; Grain size; Heating; High temperature effects; Hydrogen; Hydrogen gas sensor; Impact analysis; Junctionless FinFET; Logic gates; Metals; Process variation; Reliability; Self-heating effect; Semiconductor devices; Sensors; Service life assessment; Threshold voltage; Tin; Work functions
• ISSN: 2475-1472; 2475-1472
• DOI: 10.1109/LSENS.2023.3309263

FET-based sensors are essential for environmental monitoring, industrial analyte detection, medical diagnosis, etc. This letter unveiled the process variation, self-heating-induced performance barrier, and aging issues of the Junctionless FinFET-based hydrogen (H 2 ) gas sensor. Using Sentaurus TCAD, following gate work function modulation owing to H 2 gas concentration (in ppm), we analyzed: (i) the impact of the self-heating effect (SHE) on sensing characteristics; (ii) the impact of different metal grain sizes on work function variation (WFV); (iii) impact of random-dopant fluctuation (RDF); and (iv) device's end-of-lifetime (EOL) to predict the aging. As proof of concept, the Junctionless device was fabricated and found to sense hydrogen with a response of (23.59±1.2)% for 1.0 ppm of the gas, which agrees with our simulation results. The observed threshold voltage sensitivity is a maximum of ∼124.43% for 1.02 ppm. Thus, the proposed analysis would provide a deeper insight into a FinFET-based H 2 gas sensor from a reliability perspective.