Solid-State Electronics, Vol.47, No.6, 1045-1053, 2003
A model for tunneling current in multi-layer tunnel dielectrics
In this paper, we present a model for the tunneling currents through multi-layer stacks based on the independent electron approximation and using an Airy functions based transfer matrix formalism. The transmission coefficient of a tunneling electron is exactly calculated using a simple compact quasi-analytical formula. Comparison with the traditional WKB models reveals differences for particular stack structures. This model is applied to the analysis of multilayer tunnel dielectrics that aim at replacing the conventional tunnel oxide in non-volatile memory devices. Analysis of the tunneling current for dual-layer stacks shows possibilities for higher speed and/or lower voltage programming, which can be achieved with high-k materials considered for SiO2 replacement as gate dielectric. (C) 2003 Elsevier Science Ltd. All rights reserved.
Keywords:tunneling current;multi-layer tunnel dielectrics;Airy functions;non-volatile memory devices