Field Effect Transistors With Semiconductor-Sensitized Gate for High-Sensitivity Hydrogen Detection

The increasing popularity of hydrogen (
$\text{H}_{{2}}{)}$
energy has led to a growing demand for highly sensitive and reliable
$\text{H}_{{2}}$
sensors. In this work, we present a field effect transistor (FET)
$\text{H}_{{2}}$
gas sensor with a semiconductor-sensitized gate and achieved low subthreshold swing and significant current modulation effect. The FET-based sensor demonstrated excellent
$\text{H}_{{2}}$
sensitivity, with a response of 62.8–250-ppm
$\text{H}_{{2}}$
gas at 180 °C. An equivalent model of the sensor was also established to study the sensing mechanism behind the FET-based
$\text{H}_{{2}}$
sensor. The results suggest that the interaction of the gas-sensitive film with
$\text{H}_{{2}}$
molecules leads to a change in the potential of the floating gate (FG), which in turn modulates the channel current and allows the sensor to detect different
$\text{H}_{{2}}$
concentrations. The proposed structure of the FET-based gas sensor offers significant potential for improving the sensitivity of
$\text{H}_{{2}}$
detection.