Multilayered temperature/humidity sensitive thick-film p-i-p~+ structures based on spinel-type semiconducting ceramics of different chemical composition (Cu_(0.1)Ni_(0.1)Co_(1.6)Mn_(1.2)O_4 with p~+-type of electrical conductivity, Cu_(0.1)Ni_(0.8)Co_(0.2)Mn_(1.9)O_4 with p-type of electrical conductivity) and magnesium aluminate i-type MgAl_2O_4 ceramics, as well as temperature-sensitive p-p~+ and p-p~+-p structures were prepared and studied. Temperature-sensitive thick-film structures possess good electrophysical characteristics before and after long-term ageing test at 170 °C and the drift of electrical resistance is no more than 1 %. Increase of the quantity of thick-film layers (from two to three) results in the improvement of the temperature sensitivity of thick-film structures. It is shown, that just prepared humidity-sensitive thick films in one-layered form posses good linear dependence of electrical resistance on relative humidity without hysteresis in the range of 40-99 %. Low sensitivity of these elements at normal physical condition is connected with the degradation process over contact area. Integrated p-i-p~+ thick-film structures are stable in time and can be successfully applied for integrated environmentntal sensors.
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