A Modified Herman Model for the Prediction of Time-Dependent Dielectric Breakdown (TDDB) Characteristics of Low-k/ULK Interconnect Dielectrics from Dual-Voltage Ramp Dielectric Breakdown (DVRDB) Test

摘要

We present a modified Berman model that relates breakdown voltage distributions, from dual voltage ramp dielectric breakdown (DVRDB) test, to the distribution of time-to-fail (TTF) during constant voltage stress (CVS) conditions, assuming that dielectric failure behavior under a constant voltage stress follows the square-root E-model. The methodology presented in this work demonstrates a fast and very effective way of extracting the voltage acceleration parameter (i.e., electric field dependence) and predicting TTF under CVS TDDB test conditions. Both low-k (k=2.7) and ULK(k<2.5) DVRDB and CVS TDDB data of 45nm and 32nm dielectrics are presented, along with the model predictions and Monte-Carlo simulation results.