Synergetic Effect of Doping and Oxygen Vacancies to Realize Higher Permittivity and Lower Leakage for DRAM Capacitors: A First-Principles Study

A dielectric material with higher permittivity and lower leakage is required to meet the demands of three-dimensional (3D) DRAM. The t -phase <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$\text{HfO}_{2}$</tex> has higher permittivity but instability. Our First-principles calculations reveal that doping Y and the associated oxygen vacancies (Vo) play a critical role in phase stability. Additionally, defect states induced by Vo can be passivized at charge balance state to enable large bandgap, suppressing leakage currents. Our findings offer a feasible technical pathway for further 3D DRAM.