Multilayered ALD HfAlOx and HfO2 for High-Quality Gate Stacks

This paper has demonstrated a high-quality HfO2-based gate stack by depositing atomic-layer-deposited HfAlOxalong with HfO2in a layered structure. In order to get a multifold enhancement of the gate stack quality, both Al percentage and distribution were observed by varying the HfAlOxlayer thickness and its location in the gate stack. It was found thatit. When devices were stressed in the gate injection mode at a constant voltage stress, the dielectrics with Al/(Hf+Al)%FB, and stress-induced leakage current. The time-dependent dielectric breakdown characteristics showed a higher charge to breakdown and an increase in the extracted Weibull slope β, which further confirms an enhanced dielectric reliability for devices with <; 2% Al/(Al + Hf)%.