Study of an electroless plating (EP)-based Pt/AlGaN/GaN Schottky diode-type ammonia sensor

An ammonia sensor based on a Pt/AlGaN/GaN Schottky diode, fabricated by the electroless plating (EP) technique, has been studied in this work. The studied sensor device shows a significant sensing response under an extremely low ammonia concentration of 10 ppb NH3/air at 115 °C. As exposed to a 1000 ppm NH3/air gas, a high sensing response of 16.22 with a response (recovery) time of 8.73 (2.04) min is obtained. Even at room temperature (25 °C), the studied sensor exhibits good ammonia sensing performance with a sensing response of 2.68 at 1000 ppm NH3/air and a low detection limit of 1 ppm NH3/air. Based on the excellent sensing performance and inherent advantages of low-power consumption and low-temperature operation, the studied sensor device provides the promise for high-performance ammonia sensing applications.