Sensors for other hydrogen-containing gases

Apart from hydrogen and ammonia, MOS-based devices have also been shown to respond to a number of other hydrogen-containing gases. 

The palladium-gate devices have been shown to respond to hydrogen sulphide (28). The devices were shown to follow a half-power law similar to the response to hydrogen. The response was considered to be due to the formation of atomic hydrogen from the catalytic dissociation of the hydrogen sulphide (again similar to the response of hydrogen). 

Arsine has also been detected by palladium-gate MOS devices (29). These devices were different from the hydrogen-sensitive devices (although they also respond to hydrogen) in that the gate electrode was fabricated with a series of holes with a diameter of 2 gm along its length. The sensors were shown to be able to detect at least 1 ppm of arsine in air. No response mechanism was proposed for these devices. 

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