Defects in HfO₂ Based Dielectric Gate Stacks

Abstract

We report on both conventional electron paramagnetic resonance (EPR) measurements of fully processed HfO 2 based dielectric films on silicon and on electrically detected magnetic resonance (EDMR) measurements of fully processed HfO 2 based MOSFETs. The magnetic resonance measurements indicate the presence of oxygen vacancy and oxygen interstitial defects within the HfO 2 and oxygen deficient silicons in the interfacial layer. The EDMR results also indicate the generation of at least two defects when HfO 2 based transistors are subjected to significant negative bias at modest temperature. Our results indicate generation of multiple interface/near interface defects, likely involving coupling with nearby hafnium atoms.