A physical manifestation of interfacial roughness pitfalls in assessing dielectric TDDB lifetimes

A practical model of physically interpreting electrical responses was proposed to quantify the enhancement effects of local electrical fields along the complex poly-oxide-poly interfaces. In revealing the unique test polarity dependence of breakdown voltage and IV characteristics, the excellent agreement between TCAD simulations and measurements have fully validated the existence of locally enhanced fields. As a result, the reliability pitfalls, i.e., the artificially alternated model-fitting parameters, have been manifested for the first time in assessing the TDDB lifetimes under locally enhanced electrical fields due to the interfacial roughness.