Current-Driven Monte Carlo Simulation of Conduction in Switching Chalcogenides

The I(V) characteristics of amorphous chalcogenides usually show a negative differential conductance region, which makes the material switch from a high-resistive to a high-conductive state. This feature is of the utmost importance for adopting these materials in the manufacturing of solid-state memory devices. We propose here two complementary models for the interpretation of the switching mechanism, both stemming from and updating the literature analysis. The former is based on macroscopic equations that can be solved analytically; the latter is a current-driven three-dimensional Monte Carlo simulation of the device. A critical analysis of the two models is also performed in order to identify the fundamental conditions accounting for the voltage snap-back of the I(V) curve.