Sensor applications based on AlGaN/GaN heterostructures

Gallium Nitride (GaN) belongs to III-N family of compound semiconductors, which albeit new, is well-established material system in the fields of high power, high temperature electronics and optoelectronics. Also, its properties such as high mobility, surface sensitivity, non-toxicity, thermal endurance, low power consumption make it an ideal material for realizing sensors. This paper provides a review on the significant research work done in the field of GaN based sensor technologies. We classified the work done so far, according to the applications and the different types of parameters being measured. The challenges faced by the current sensing systems and future opportunities are also briefly explained for a variety of applications viz. radiation sensors, mechanical sensors, gas sensors, biosensors, chemical sensors and high temperature Hall-effect sensors etc. Additionally, the sensing mechanism of various sensors is explained. This paper can supply initial reading material for beginners and research students working on GaN heterostructure based sensor applications.