Semiconductor sensors for the detection of fluorocarbons, fluorine and hydrogen fluoride Original Research Article

The sensitivity of metal–insulator–semiconductor structure gas sensors based on silicon or silicon carbide to different fluorine-containing gases was studied in the temperature range 20–530°C. Silicon based gas sensors could be used for the determination of fluorine and hydrogen fluoride at room temperature. The sensitivity to fluorine is 28.0±0.5 mV/lg(p(F2)), the sensitivity to HF is 44.4±1.6 mV/(p(HF)), and the detection is about 10 ppb in both instances. High temperature silicon carbide sensors can be applied for the determination of fluorine and fluorocarbons (CF3CH2F, CF3CCl3, CF3CH2Cl, CHClF2, CCl2F2, CCl3F) up to 530°C. The sensor signal for fluorocarbon concentration measurements demonstrates a Nernstian concentration dependence. The detection limit for these gases is ca. 10 ppm.