Phenomenological theory to model leakage currents in metal-insulator-metal capacitor systems

A phenomenological model intended to provide a description of leakage behavior in metal-insulator-metal (MIM) capacitor devices is presented. The model is able to predict both transient and steady state leakage currents under constant voltage bias conditions (the J-t characteristics), as well as J-V characteristics for a given voltage sweep schedule. The electronic transport processes currently implemented in the model include trap assisted tunneling (TAT) of electrons from the electrode to defect or trap states in the dielectric, modified Poole-Frenkel (MPF) emission of part of the trapped electrons to the conduction band of the dielectric, and Schottky emission of Fermi level electrons directly from the electrode to the conduction band of the dielectric. The model is able to predict many of the observed features, including characteristic slopes in J-t and J-V plots, and dependences of the leakage current on dielectric thickness, temperature and the Schottky barrier height. (C) 2003 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.