Spectroscopic Studies of Electronically Active Defects in Transition Metal Oxides for Advanced Si Devices

Abstract

Based on spectroscopic studies, and guided by ab initio theory, the electron and hole traps in HfO2 and other transition metal elemental oxides e.g., TiO2, are assigned to O‐atom divacancies, clustered at internal grain boundaries. Engineering solutions for defect reduction are identified: i) deposition of ultra‐thin, < 2 nm HfO2 and phase separated Hf silicate dielectrics, in which grain boundary formation is suppressed by effectively eliminating inter‐primitive unit cell π‐bonding interactions, and ii) non‐crystalline Zr/Hf Si oxynitrides without nanocrystalline grain boundaries.