MINORITY-CARRIER EXCLUSION

The paper deals with a current-controlled non-equilibrium process, whereby the influx of minority carriers into a semiconducting material is smaller than the rate required for normal conduction in the undisturbed, homogeneous bulk. It is shown, within the framework of a “small signal theory”, how the corresponding concentration and field contours depend on the carrier lifetime, the mobility ratio and the current composition contact characteristics (via the exclusion ratio). The departures from electronic equilibrium can lead to a total resistance increase or a decrease, depending on the detailed combination of parameters.