Oscillation in Semiconductors with a Dumbbell-Shaped Structure

Abstract

A new model of current oscillation observed in the current saturation regime of the current-voltage characteristic in semiconductors with a dumbbell-shaped structure is proposed. As the electron and hole drift velocities deviate from Ohm's law, an electric double layer is formed on the anode side of the narrow region of a sample and a negative resistance region appears on the cathode side. These formations in the sample cause the current oscillation. Experimental measurements of the potential distributions in the sample are carried out for n-type germanium and it is shown that these results can be explained well by the proposed model.