A complementary molecular-model (including field and current) for TDDB in SiO2 dielectrics

A molecular physics-based complementary model, which includes both field and current, is introduced to help resolve the E versus 1/E TDDB model controversy that has existed for many pars It is shown here that either TDDB model can be valid for certain specified field, temperature, and molecular bonding-energy ranges. For bond strengths < 3eV, the bond breakage rate is generally dominated by field-enhanced thermal processes at lower fields and elevated temperatures and the E-Model is valid. At higher fields, lower temperatures and higher bond strengths the bond breakage mechanism must be hole-catalyzed and the TDDB physics is described well by the 1/E - model. However, neither the simple E-model nor 1/E-model works well for oxide thickness below t(ox) < 4 nm where direct tunneling effects dominate. (C) 2000 Elsevier Science Ltd. All rights reserved.