Bulk Grain Resistivity of ZnO-Based Varistors

    loading  Checking for direct PDF access through Ovid


We study the temperature dependence of grain resistivity in ZnO ceramic varistors (300–430 K), finding a positive temperature coefficient (PTC). We devise a high-frequency procedure that allow us to obtain the concentration and energy position of the shallow donor. The observed behavior is consistent with a shallow donor approaching complete ionization, and with an electron mobility mainly controlled by lattice (both optical and acoustical) scattering. The impact of this behavior on varistor performance under high-current pulse loads is discussed.

Related Topics

    loading  Loading Related Articles