Atomistic simulation study of high-κ oxide defects for understanding gate stack and RRAM reliability

High-κ Oxide Defects in the MOSFET gate stack and RRAM cell severely impact the device reliability. In this work, we conducted first-principles modeling and simulation to investigate BTI performance in the SiON, HfO2 and La doped HfO2 MOSFET gate stacks. The properties of VO, Oi and VO-Oi defect pair are studied, and unique behaviors of these defects which attribute to the BTI degradation in the aforementioned device gate stack are presented. Thereafter, the understanding of the defects in the hafnium oxide is extended to the RRAM study. We exhibit the key role of the forming step in generating the switchable conductive filament, and meanwhile an alternative method by using of Pt as the bottom electrode to mediate the conductive filament generation is introduced.DOCTOR OF PHILOSOPHY (EEE