Extreme environments in industries such as aerospace require sensors to measure factors under harsh conditions. With that in mind, a team of researchers at the University of Houston developed a sensor that has been proven to work in temperatures as high as 1650°F (900°C).
The research team previously developed III-N piezoelectric pressure sensor using single-crystalline gallium nitride (GaN) thin films for harsh-environment applications. However, the sensitivity of the sensor decreases at temperatures higher than 662°F (350°C). The team believed the decrease in sensitivity was due to the bandgap – the minimum energy required to excite an electron and supply electrical conductivity – not being wide enough. To test the hypothesis, they developed a sensor with aluminum nitride (AlN).