Stress-Enhanced Ferroelectric Properties in Flexible Hf_0.5Zr_0.5O₂ Devices With Low Thermal Budget

HHigh-performance flexible HfO<sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub>-based ferroelectric devices with low thermal budget are essential for the large-scale integration and application of flexible electronic systems. In this work, the ferroelectricity of Hf<sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">0.5</sub>Zr<sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">0.5</sub>O<sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> (HZO) devices under a low annealing temperature of 400 °C was enhanced by stress effect. Compared with Si-based HZO devices, flexible HZO devices exhibit a higher remanent polarization (P<sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">r</sub>) value of 28.5 μC/cm<sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> and superior endurance, with only a 5.6% degradation in Pr after 10<sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">10</sup> cycles. Furthermore, the flexible HZO devices were annealed under bending, resulting in an increased P<sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">r</sub> value of 31.4 μC/cm<sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> and a reduced coercive field (2E<sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">c</sub>) of 2.6 MV/cm. This work provides effective technical support for achieving high-performance flexible HZO devices.