Gate oxide reliability: the use of simulation to quantify important aspects of lifetime projection from TDDB data

Abstract

We use simulations to study the consequences of applying the effective thickness theory of oxide reliability to both the Berman and Chen oxide electric field models for the time-to-failure of Time Dependent Dielectric Breakdown (TDDB) data. The focus is on understanding the effects of errors in the analysis of TDDB data on the accuracy of lifetime prediction. There are three aspects which are studied for their effects on the accuracy of lifetime prediction (which are in addition to the frequently discussed field model sensitivity): extrapolation of the cumulative distribution function (CDF) F to small values of F (as required by specific reliability criteria); conversion from measured gate voltage V/sub g/ to internal oxide voltage V/sub ox/; polarity dependence.