Patent ID: 11921074
Assignee: INFINEON TECHNOLOGIES AG
Field: Measurement (Instruments)
Classification: CPC G | IPC G

Claim 21:
22. A method of operating a gas sensitive device comprising: a substrate structure; and a gas sensitive capacitor comprising a first capacitor electrode in form of a gas sensitive layer on a first main surface region of an insulation layer, a second capacitor electrode in form of a buried conductive region below the insulation layer, and a cover layer disposed on top of the insulation layer, wherein: the insulation layer is arranged between the first and second capacitor electrode, the gas sensitive layer comprises a sheet resistance that changes in response to adsorption or desorption of gas molecules, and the cover layer has at least one common plane with the first capacitor electrode, the cover layer surrounds the first capacitor electrode in the at least one common plane leaving the entire first capacitor electrode uncovered by the cover layer, the method comprising:
applying an AC signal to the first capacitor electrode; and
reading out a signal between the first capacitor electrode and the second capacitor electrode, wherein the signal read out comprises information on the sheet resistance of the gas sensitive layer of the first capacitor electrode due to the adsorbed or desorbed gas molecules.