SMOKE SENSOR ON THE BASE OF BI2O3 SESQUIOXIDE

The proposed smoke sensing element is a thin film of bismuth sesquioxi de made by different deposition methods by use of a corresponding hear treatment, The resistance of thin films placed in smoke medium is cha nged by about five orders of the magnitude at room temperature. The fi lm's influence on neutral and charged solid smoke particles on the thi n film resistance was investigated. It is shown that the contribution of the particles on the resistance is negligible up to 30% of the smok e concentration in air and the sensitivity of the samples investigated is caused by gases, formed by the combustion.