Mechanisms of detection on tin oxide gas sensors

Model of the thickness effect of SnO2 thick film on the detection properties

“…As reported previously, Choe [8] has proposed an interpretation of such behavior by a varying contribution of the depleted zone compared to the bulk, depending on the thickness. Taking into account other studies dealing with space charge areas [11,13,14] and influence of metallic electrodes [15][16][17], we have focused our researches on these phenomena which can explain complex behavior observed with thickness variation. Our main results are reminded here as they constitute the basis of development of the geometrical model proposed in the next paragraph.…”

“…Analytical expressions are quite complicated, so we have summarized the types of the mathematical functions obtained for G air and G gas versus the sample thickness "e" (relations [10][11][12][13][14] and the corresponding relative variations of the normalized response S in Table 1. It can be seen that the proposed model leads to complex variations of S versus sample thickness.…”

Chemical sensors

“…The single most important fact about conductometric sensors is that they include the commercially most successful sensors for manangement of the fuel and oxygen in combustion engines. The theory and the optimum operating conditions of thin film Sn02 sensors have been discussed in many papers (112,291,292,293). The steady-state diffusion model for Ti02 sensor applies to a large extent also to other oxide-type sensors (294).…”

“…A humidity sensor based on surface conductivity of A1203 has been proposed (317a). Various ways of fabrication have been examined, such as by decomposition of (CH4)4Sn (292,302), or growth of Sn02 whiskers (317be. The latter sensor shows good sensitivity for flammable gases for whiskers 5 and thicker.…”

Development of a handheld sensor system system for the online measurement of hydrogen peroxide in aseptic filling systems

“…In this case, the high cross‐sensitivity of semiconductor sensors to oxidising and reducing gases can be used to detect H 2 O 2 . These sensors tolerate gas temperatures up to 500 °C and high concentrations of H 2 O 2 , but the disadvantages of these sensors are strong drift and high cross‐sensitivity towards humidity 15–20.…”