Low-frequency dispersion in semi-insulating systems

Abstract

At sufficiently high temperatures all insulators tend to become semi-insulating due to increasing numbers of slowly mobile charges. The dielectric properties of such materials show a characteristic "signature" called low-frequency dispersion (LFD) differing drastically from direct current (dc) conduct in parallel with a capacitor and also from the Maxwell-Wagner process (MW) which in effect represents a series combination of a resistor Ro and a capacitor C0.