A high sensitivity solid state sensor for H2detection in oxygen-rich ambients at room temperature

A highly sensitive solid state sensor for hydrogen detection in oxygen-rich ambient at room temperature is described. The sensor structure is of the form of Metal/Active Insulator/ Metal (MIM), with a low pressure CVD deposited TiOxas the key active insulator layer and Pd as the gate metal. The TiOxat the Pd/TiOxinterface is reduced upon hydrogen adsorption, which in turn causes a large modification of the barrier in TiOxat the Pd/TiOxinterface. The device sensitivity is extremely large and a function of the hydrogen partial pressure in oxygen. The low detection limit is found to be less than a few PPM H2in O2.