Etude, conception et réalisation de capteurs à base de matériaux céramiques.

Abstract

Varistors are electrical components with variable resistivity depending on the electric field applied to them. These components are typically used in surge protection devices. The objectives of this work are to study the influence of the sintering temperature on the electrical properties of the material as well as to show the advantages and disadvantages compared to a conventional sintering method. To do this, zinc oxide varistors doped with Bi2O3, MnO2, Cr2O3, Sb2O3, Co3O4 and SiO2 were developed by a ceramic method and were sintered for different temperatures (1280, 1300, 1320, and 1350°c). Their characterization was done by DRX, MEB, and I (V). The samples obtained depend strongly on the production conditions (sintering temperature), the more the sintering temperature increases, the more the grain size increases. The grain size of the doped ZnO varistors obtained varies from 2.57 to 6.84 μm. The electrical characterization of these samples shows that they exhibit a non-linear behavior of varistor with a coefficient of 33.61. In addition, the threshold field is 2991.56v / cm for the temperature of 1280 ° C. These results validate the possibility of miniaturization of varistors for their application in microelectronics.