Gas sensor used for detecting hydrogen comprises pn-diode having sequence of p- and n-doped semiconductor layers, and devices for determining electrical resistance of semiconductor

摘要

A gas sensor for detecting hydrogen comprises a sequence of p- and n-doped semiconductor layers (11, 12, 13); devices (15) for determining the electrical resistance of the semiconductor layers; and a sensitive layer (14) which influences the electrical resistance of the semiconductor layers depending on the hydrogen concentration in the gas under investigation. The gas sensor is a pn-diode. An Independent claim is also included for a process for detecting hydrogen in which a semiconductor element (10) (a pn-diode) having a sensitive layer is brought into contact with a gas and the electrical resistance is measured. Preferred Features: The gas sensor is made from a semiconductor material having large band gaps, especially SiC and/or group III nitrides. The semiconductor layers are doped so that a layer sequence gate-p-n-n<+> is present in the gas sensor and the gate is formed by the sensitive layer.