Statistical simulation of leakage currents in MOS and flash memory devices with a new multiphonon trap-assisted tunneling model

A new physics-based model of leakage current suitable for MOS and Flash memory gate oxide is presented in this paper. This model, which assumes the multiphonon trap-assisted tunneling as conduction mechanism, calculates the total leakage current summing the contributions of the percolation paths formed by one or more aligned traps. Spatial positions and energetic levels of traps have been randomly generated within the oxide by a random number generator which has been integrated into the model. Using this model, statistical simulations of leakage currents measured from both MOS and Flash EEPROM memory tunnel oxides have been carried out. In this way, experimental leakage current distributions can be directly reproduced, thus opening a wide range of useful applications in MOS and Flash EEPROM memory reliability prediction.

I. Introduction

In the last years, the interest in studying oxide leakage current has grown significantly for two main reasons.