MODEL BASED ON TRAP-ASSISTED TUNNELING FOR 2-LEVEL CURRENT FLUCTUATIONS IN SUBMICROMETER METAL SILICON DIOXIDE SILICON DIODES

A new model is suggested to explain the characteristics of discrete two-level current fluctuations (TLFs) in metalsilicon-dioxidesilicon tunnel diodes. The model is based on trap-assisted tunneling via a single-electron trap. The trap does not act merely as a point charge in the oxide, but can function as an intermediate state for electrons that tunnel from the metal to the silicon. We show that this model can explain the large fluctuation amplitudes, and we use an atomic relaxation effect to account for the thermally activated capture and emission time constants found in our measurements. Because of the relative simplicity of the model, quantitative comparisons with experiments are possible. © 1990 The American Physical Society.