Development of GaN-based micro chemical sensor nodes

Sensors based on III-N technology are gaining significant interest due to their potential for monolithic integration of RF transceivers and light sources and the capability of high temperature operations. We are developing a GaN-based micro chemical sensor node for remote detection of chemical toxins, and present electrical responses of AlGaN/GaN HEMT (high electron mobility transistor) sensors to chemical toxins as well as other common gases. Upon exposure to a chemical toxin, the sensor showed immediate increase in source-drain current (Ids). The electrical response of the sensor was clear, reproducible and characteristic of the concentration of the analyte. This is the first time that electrical responses of chemical toxins are measured with a GaN-based microsensor. Detailed analysis on response time, sensitivity and temperature dependence will be discussed