Temperature Sensitive Spinel-Type Ceramics in Thick-Film Multilayer Performance for Environment Sensors

Temperature sensitive thick films 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 $p^{+}$-types of electrical conductivity), $Cu_{0.1}Ni_{0.8}Co_{0.2}Mn_{1.9}O_{4}$ (with p-types of electrical conductivity) and their multilayer $p^{+}$-p structures were fabricated and studied. These thick-film elements possess good electrophysical characteristics before and after long-term ageing test at 170°C. It is shown that degradation processes connected with diffusion of metallic Ag into film grain boundaries occur in one-layer p- and $p^{+}$-conductive thick films. The $p^{+}$-p structures were of high stability, the relative electrical drift was not greater than 1%.