Since the appearance of the Japanease semiconductor sensors the European market has been dominated by imported sensors. Early applications as CO-, methane, or propane warning boxes for use in private homes did not attain a high reputation for reliability. In tests of gas supplying companies such sensor boxes equipped with simple electronics checking only a conductance threshold failed to survive a period of about a year. Meanwhile some European companies produce semiconductor gas sensors with a closer distance to the market allowing to stabilize key properties for reliable warning systems. One example will be described in some detail, a detection system for smouldering fires featuring three tin oxide sensors and an intelligent evaluation system. This system in installed in fossile power plants. Another example is a methane sensor based on gallium oxide featuring an overlayer improving the selectivity. The conductance of galium oxide is not dependent on potential barriers between the grains. Therefore, this sensor material shows a stability of the conductance value in the agsence of the analyse gas which is even superior to the stability of a platinum thin film heating element ordinarily used to stabilize the temperature of a sensor element.
JavaScript jest wyłączony w Twojej przeglądarce internetowej. Włącz go, a następnie odśwież stronę, aby móc w pełni z niej korzystać.