Breakdown in the metal/high-k gate stack: Identifying the “weak link” in the multilayer dielectric

Abstract

We apply a systematic approach to identify a high-k/metal gate stack degradation mechanism. Our results demonstrate that the SiO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> interfacial layer controls the overall degradation and breakdown of the high-k gate stacks stressed in inversion. Defects contributing to the gate stack degradation are associated with the high-k/metal-induced oxygen vacancies in the interfacial layer.