SAW Sensor for Mercury Vapour Detection

Mercury is the element commonly applied in industry. Because of poisoning properties the monitoring of the mercury vapour concentration in the environment is very important. Mercury forms amalgams in connection with gold that causes a change in the electrical resistance and mass of the gold specimens. This e ect was applied to measure mercury vapour concentration in the environment using surface acoustic wave technology. Two kinds of surface acoustic wave mercury sensors have been described in the paper. First one utilizes a thin lm of gold deposited between aluminium interdigital transducers and re ectors of two-port surface acoustic wave resonator, and the second one golden interdigital transducers and re ectors without any sensitive lm between them.