TOWARDS 0.5 nm EOT SCALING OF HfO_2/METAL ELECTRODE GATE STACKS

摘要

This paper presents results demonstrating the combination of a scaled HF-last/NH3 anneal bottom interface, scaled HfO2 high-k dielectric, and metal gate electrode to create gate stacks having an equivalent oxide thickness of 0.51 nm after a 1000C/IOS anneal. Transistors using this gate stack show gate current density two decades below that projected for a SiO2 transistor of similar EOT and good transistor characteristics. These results demonstrate that the use of HfO2 / metal gate transistors in this EOT regime will require changes in process, characterization, design, and reliability methodologies in order to successfully implement these structures into the semiconductor roadmap.