摘要
Ferroelectric (FE) HfZrO<sub>x</sub> (HZO) integrated with ZrO<sub>2</sub> interlayer and bottom layer was explored as the new stack (TiN/HZO/ZrO<sub>2</sub>/HZO/ZrO<sub>2</sub>/TiN) for FE capacitors processed at 400 &null The capacitors show high remnant polarization (2P<sub>r</sub>) of 37 &null <sup>2</sup> with wake-up free behavior up to 10 <sup>8</sup> long-pulse cycles. High orthorhombic phase (o-phase) ratio is confirmed to be the root cause of wake-up free behavior and both ZrO<sub>2</sub> layers play the pivotal role as a nucleation layer for o-phase HZO formation while providing tensile stress due to large thermal expansion coefficient mismatch with HZO. Furthermore, capacitors also exhibit quadruple-level cell (4 bits/cell) operation with small device-to-device variation after long cycling. The promising results make the stack eligible for high-performance, high-reliability and high-density embedded memory applications.