Design and Investigation of Double Gate Field Effect Transistor Based H2 Gas Sensor Using Ultra-Thin Molybdenum Disulfide

• Published in: SILICON Vol. 15; no. 3; pp. 1193 - 1202
• Main Authors: Karmakar, Ananya, De, Arpan, Sen, Dipanjan, Chanda, Manash
• Format: Journal Article
• Language: English
• Published: Dordrecht Springer Netherlands 01-02-2023; Springer Nature B.V
• Subjects: CAD; Chemistry; Chemistry and Materials Science; Computer aided design; Environmental Chemistry; Field effect transistors; Gas pressure; Gas sensors; Inorganic Chemistry; Lasers; Materials Science; Molybdenum; Molybdenum disulfide; Optical Devices; Optics; Original Paper; Palladium; Photonics; Polymer Sciences; Semiconductor devices; Sensors; Simulation models; Surface roughness; Thermal noise; Threshold voltage; Transistors; Two dimensional materials; Work functions; Field effect transistor; Schottky barrier effect; Sensitivity; Hydrogen gas sensor; 2D materials
• ISSN: 1876-990X; 1876-9918
• DOI: 10.1007/s12633-022-02103-w

In this article, a low-power hydrogen (H
2
) gas sensor has been proposed using a two-dimensional (2D) material based Double Gate Field Effect Transistor (2D-FET). It is imperative to highlight that the conventional three-dimensional (3D) materials cannot be scaled down to an ultra-low dimension due to the presence of dangling bonds, surface roughness scattering etc. This creates a major challenge in developing low-dimensional sensors for next generation sensing and computing. In this context, we have developed an extensive simulation model, which articulates the physical phenomena behind a catalytic metal gate-based hydrogen gas sensor using a 2D-FET. A 5 nm thin Molybdenum disulfide (MoS
2
) film has been used as the channel material for the proposed 2D-FET based gas sensor. The sensor has been modelled by emphasizing on the catalytic metal (Palladium) gate approach, where the work function of the gate metal deposited on top of the channel region varies after the absorption of the hydrogen gas. Moreover, the Technology Computer Aided Design (TCAD) based gas sensor model has been developed by considering a change in the pressure of H
2
gas as well. We have also highlighted the effect of Metal/MoS
2
contact on sensor performance. In terms of the performance, a maximum threshold voltage (V
th
) shift of 100 mV has been obtained against a gas pressure of 10
−10
 torr, whereas the maximum percentage of change in I
ON
/I
OFF
is 100. Lastly, the authors have shown the thermal noise characteristics of the gas sensor.