Selective-Ferroelectricity-Defining Method Utilizing Directional Oxygen Plasma Treatment for Optimizations of Hf_0.5Zr_0.5O₂-Based Memory Devices

We present a method to control the ferroelectricity in specific regions of <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$\text{Hf}_{0.5} \text{Zr}_{0.5} \mathrm{O}_{2}$</tex> (HZO) through directional oxygen plasma treatment. Using this method, the ferroelectricity can be selectively eliminated in the treated areas, and leakage currents up to 10 times lower than untreated areas can be achieved after rapid thermal annealing (RTA), allowing HZO in the treated regions to be used as the ideal gate dielectric. This method streamlines the fabrication process by reducing the number of steps needed to design and prototype ferroelectric devices. In this way, it can facilitate the integration of ferroelectric devices with regular access transistors and has promising potential to simplify fabrication process and reduce cost in mass productions.