Ji Soo Kim1,Maximilian Becker1,Nives Strkalj1,2,Megan Hill1,3,Ziyi Yuan1,Judith MacManus-Driscoll1
University of Cambridge1,Institute of Physics2,Lund University3
Ji Soo Kim1,Maximilian Becker1,Nives Strkalj1,2,Megan Hill1,3,Ziyi Yuan1,Judith MacManus-Driscoll1
University of Cambridge1,Institute of Physics2,Lund University3
Ferroelectric hafnium oxide is of great interest in the semiconductor industry due to its complementary metal-oxide-semiconductor compatibility and scalability. It has potential to be used as actuator, sensors, transducers, memories, etc. Out of all the dopants studied, zirconium doped hafnium oxide, Hf<sub>0.5</sub>Zr<sub>0.5</sub>O<sub>2</sub> (HZO), has been the most promising and widely investigated composition with reported remanent polarisation (P<sub>r</sub>) of ~ 20 μC/cm2 and coercive field (E<sub>c</sub>) of ~ 1 MV/cm. However, there are limitations with ALD-grown ferroelectric HZO films in terms of wake-up effect, endurance and tuning of P<sub>r</sub> and E<sub>c</sub> for specific application such as ferroelectric random-access memory (FeRAM), ferroelectric field effect transistor (FeFET), negative capacitance field effect transistor (NCFET), and many more. In this work, model systems of HZO films were deposited by pulsed laser deposition (PLD) in which the epitaxial rhombohedral ferroelectric phase was stabilised. All the films show wake-up free ferroelectric behaviour with P<sub>r</sub> > 7 μC/cm<sup>2</sup>. With increase in laser fluence from 0.5 to 1.3 J/cm<sup>2</sup>, EC increased from ~ 2.7 MV/cm to ~ 3.3 MV/cm. In order to understand the origin of such change in ferroelectric properties, we separate out individual influences of O content, strain and microstructure via x-ray photoelectron spectroscopy, x-ray diffraction, and scanning tunnelling electron microscopy.