Gas sensor with improved selectivity

Abstract

The present invention relates to a gas sensor (1) for detecting gases, with at least one gas-sensitive layer which is applied to a substrate (2), wherein at least one conductor track (3) for contact-connecting the layer is also provided on the substrate (2), and wherein the conductor track (3) is formed from a doped metal oxide material with non-catalytic properties in order to avoid the conductor track (3) influencing the detection of the gas. This avoids the disadvantages of the prior art and provides contact-connection of the gas-sensitive layers which does not influence the sensitive properties when detecting the gas by means of the layer.

Description

technical field [0001] The invention relates to a gas sensor for detecting gases, which has at least one gas-sensitive layer applied to a substrate, wherein at least one electrically conductive track is also arranged on the substrate for contacting the layer. Background technique [0002] Currently, cost-effective thick-layer metal oxide sensors are used for the detection of various gases and vapors. What is currently observed is the ongoing trend toward thin-layer technology in order to reduce the power consumption of these sensors. For this purpose, the sensitive layer of the gas sensor exhibits a nominal layer thickness of individual nanotubes or nanoclusters of the order of less than 100 nm or even several nanometers. Furthermore, energy savings can be achieved by applying these thin structures and layers on micromechanical components. Under favorable operating conditions, the result is a reduction in power consumption by a factor of 500 compared to conventional sensor...

AI Technical Summary

Problems solved by technology

While this demonstrates that selectivity can be improved by changing the temperature, electrodes containing noble metals are also prone to oxidation, which can negatively affect the measurement results

[0010] Therefore, the use of such a gas sensor has the following problems: At higher temperatures, the metal diffuses into the sensitive layer, affecting its gas sensitivity performance

Already at low temperatures, gases react more favorably and react very early on the conductive strip, distorting sensor characteristics

Thinner layers are more sensitive to dopants and are therefore more prone to the above-mentioned problems, so that the measurement of different gases with micromechanically constructed gas sensors is more limited

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