Transient currents in pulsed metal–oxide–semiconductor tunnel diodes

Abstract

The effect of tunneling currents on the transient from deep depletion towards equilibrium in thin oxide metal–oxide–semiconductor capacitors was experimentally investigated. Very thin oxide samples exhibit similar transients for both p- and n-type substrates. This symmetry breaks down for oxide thicknesses of more than 3.5 nm. Three qualitatively different behavior patterns, depending on the oxide thickness, can be identified by the current transient curves for the n-type substrate samples. From an analysis of the associated currents, the three patterns correspond to dominance by the minority carrier tunneling, dominance by the majority carrier tunneling, and enhanced generation through impact ionization.