Performance-driven OFET design for advanced hydrogen gas sensing applications

Abstract

Hydrogen gas sensing, a crucial area of research with wide-ranging applications, was significantly advanced by the findings of this study. Because they can identify leaks and stop any risks, hydrogen (H₂) gas sensors are crucial for safety in sectors that use fuel-cell technology, hydrogen generation, and storage. They are also essential for developing H₂ as a power source and environmental monitoring. Analyzing the effects of changes in semiconductor channel thickness on the functionality of organic field-effect transistors (OFETs) in H₂ gas detection is a critical component of this study. The study concentrated on channel thickness between 15 and 45 nm, analyzing how these differences affect the sensitivity through ON and OFF current changes. In this work, a platinum (Pt) gate electrode was used to detect H₂ gas using a top-gate top-contact (TGTC) design. Hydrogen gas causes the electrical characteristics of the sensor to vary, enabling effective detection by tracking modifications in the field-effect behavior of the active layer. The simulation results show a trade-off between sensitivity, device performance, and channel thickness, highlighting the importance of optimizing the channel thickness during fabrication to increase sensitivity. Channel thickness is crucial for stability and sensitivity in OFET-based gas sensors; thinner channels are associated with lower durability, whereas thicker channels lead to lower performance. To maximize the total sensor performance, this analysis aims to achieve an equilibrium between low-cost fabrication and sensitivity. These observations provide helpful directions for the development and fabrication of extremely sensitive low-cost hydrogen gas sensors.