SiC gas sensor arrays for extreme environments

For the first time SiC-based gas sensor arrays have been demonstrated, which are capable of discriminating gas species under harsh environments. The structures utilise either a TiO₂ or HfO₂ dielectric layer and a Pt or Pd catalytic contact. We show that the defects in the dielectric dominate the response to hydrogen and oxygen, resulting in array behaviour, without the need for large numbers of catalytic metals. Simple multiple linear regression techniques can be used with the array to provide a real time prediction of the gas contents of a mixture.