Pt-AlGaN/GaN Hydrogen Sensor With Water-Blocking PMMA Layer

One of the biggest issues with GaN-based hydrogen sensors is their sensitivity to humidity in the ambient. We demonstrate that encapsulation of Pt-AlGaN/GaN Schottky diode with poly(methyl methacrylate) (PMMA) provides effective mitigation of the effects of water. Without PMMA encapsulation, the absolute current signal for detection of 500 ppm of H2 was decreased by a factor of 8 in the presence o...