UV-assisted High-sensitivity Room-temperature Pd-gated HEMT NO2Gas Sensor

AlGaN/GaN based HEMT gas sensors have been very competitive owing to their superior advantages such as compact size, high sensitivity, long lifetime, and excellent chemical and thermal stability. In this article, a Pd-gated HEMT NO
2
gas sensor was fabricated, exhibiting high sensitivity of 31% to 5 ppm and 45% to 10 ppm at room temperature. Intriguingly, such devices exhibited enhanced current change
$(\Delta \mathrm{I})$
under additional UV illumination, which is beneficial to low-noise trace concentration detection.