Magnetic resonance and internal photoemission study of trap centers in high-k dielectric films on Ge

Internal photoemission and magnetic resonance studies have been performed to investigate the charge trapping kinetics and chemical nature of defects present in ultrathin high-k dielectric films deposited on p-Ge (100) substrate. Both the band and defect-related electron states were characterized through EPR, IPE, C-V and I-V measurements under UV-illumination. The interface trap spectrum in Ge/high-k oxide systems appears to be dominated by slow acceptor states with a broad energy distribution as major contribution comes from the imperfections located in the insulating layer. However, the oxynitride samples demonstrate lower defect or trapping behavior over non-nitrided samples.